Investing in the Notes involves significant risks. You may lose a significant portion all of your initial investment. Any payment on the Notes, including any repayment of principal, is subject to the creditworthiness of UBS. If UBS were to default on its payment obligations, you may not receive any amounts owed to you under the Notes and you could lose all of your initial investment.

If the Notes are not subject to an automatic call, you may lose a significant portion or all of your initial investment. Specifically, if the Notes are not subject to an automatic call and the final level of any underlying asset is less than its downside threshold, you will lose a percentage of your principal amount equal to the underlying return of the least performing underlying asset and, in extreme situations, you could lose all of your initial investment. You will be exposed to the market risk of each underlying asset on each observation date and on the final valuation date and any decline in the level of one underlying asset may negatively affect your return and will not be offset or mitigated by a lesser decline or any potential increase in the levels of the other underlying assets.

An investment in the offering of the Notes involves significant risks. Investing in the Notes is not equivalent to a hypothetical investment in the least performing underlying asset or its underlying equity constituents. Some of the risks that apply to the Notes are summarized below, but we urge you to read the more detailed explanation of risks relating to the Notes in the “Risk Factors” section of the TACYN product supplement. We also urge you to consult your investment, legal, tax, accounting and other advisors before you invest in the Notes.

In addition, the lower the correlation is between the performance of a pair of underlying assets, the more likely it is that one of the underlying assets will decline in value to a closing level or final level, as applicable, that is less than its coupon barrier or downside threshold on any observation date or on a final valuation date, respectively. Although the correlation of the underlying assets’ performance may change over the term of the Notes, the economic terms of the Notes, including the contingent coupon rate, downside threshold and coupon barrier are determined, in part, based on the correlation of the underlying assets’ performance calculated using our internal models at the time when the terms of the Notes are finalized. All things being equal, a higher contingent coupon rate and lower downside threshold and coupon barrier is generally associated with lower correlation of the underlying assets. Therefore, if the performance of a pair of underlying assets is not correlated to each other or is negatively correlated, the risk that you will not receive any contingent coupons or that the final level of any underlying asset is less than its downside threshold will occur is even greater despite a lower downside threshold and coupon barrier. Therefore, it is more likely that you will not receive any contingent coupons and that you will lose a significant portion or all of your initial investment at maturity.

The below examples are based on hypothetical terms. The actual terms will be set on the trade date and will be indicated on the cover of the applicable pricing supplement.

The examples below illustrate the payment upon a call or at maturity for a $10 Note on a hypothetical offering of the Notes, with the following assumptions (amounts may have been rounded for ease of reference):

Example 1 — The Closing Level of each Underlying Asset is equal to or greater than its Initial Level on the Observation Date corresponding to the first Potential Call Settlement Date.

Because the Notes are subject to an automatic call on the first potential call settlement date (which is approximately six months after the trade date), UBS will pay on the call settlement date a total of $10.1625 per Note (reflecting your principal amount plus the applicable contingent coupon). When added to the contingent coupon of $0.1625 received in respect of the prior observation date, you will have received a total of $10.3250, a 3.250% total return on the Notes. You will not receive any further payments on the Notes.

Example 2 — The Notes are NOT subject to an Automatic Call and the Final Level of each Underlying Asset is equal to or greater than its Downside Threshold.

Because the Notes are not subject to an automatic call and the final level of each underlying asset is equal to or greater than its downside threshold, at maturity, UBS will pay a total of $10.1625 per Note (reflecting your principal amount plus the applicable contingent coupon). When added to the contingent coupon of $0.1625 received in respect of the prior observation dates, UBS will have paid a total of $10.3250, a 3.250% total return on the Notes.

Example 3 — The Notes are NOT subject to an Automatic Call and the Final Level of an Underlying Asset is less than its Downside Threshold.

Because the Notes are not subject to an automatic call and the final level of Underlying Asset B is less than its downside threshold, you will be exposed to the underlying return of the least performing underlying asset and at maturity UBS will pay you $4.00 per Note. When added to the contingent coupons of $0.3250 received in respect of prior observation dates, UBS will have paid you $4.3250 per Note for a loss on the Notes of 56.750%.

We make no representation or warranty as to which of the underlying assets will be the least performing underlying asset for the purposes of calculating your actual payment at maturity.

Investing in the Notes involves significant risks. The Notes differ from ordinary debt securities in that UBS is not necessarily obligated to repay the full amount of your initial investment. If the Notes are not subject to an automatic call, you may lose a significant portion or all of your initial investment. Specifically, if the Notes are not subject to an automatic call and the final level of any underlying asset is less than its downside threshold, you will lose a percentage of your principal amount equal to the underlying return of the least performing underlying asset and, in extreme situations, you could lose all of your initial investment.

You will be exposed to the market risk of each underlying asset on each observation date and on the final valuation date and any decline in the level of one underlying asset may negatively affect your return and will not be offset or mitigated by a lesser decline or any potential increase in the levels of the other underlying assets. Any payment on the Notes, including any payments in respect of an automatic call, contingent coupon or any repayment of principal, is subject to the creditworthiness of UBS. If UBS were to default on its payment obligations, you may not receive any amounts owed to you under the Notes and you could lose all of your initial investment.

MSCI ^® Emerging Markets Index ^SM

We have derived all information contained herein regarding the MSCI ^® Emerging Markets Index ^SM including, without limitation, its make-up, method of calculation and changes in its components from publicly available information. Such information reflects the policies of, and is subject to change by MSCI Inc., which we refer to as “MSCI”. UBS has not conducted any independent review or due diligence of any publicly available information with respect to the MSCI ^® Emerging Markets Index ^SM .

The MSCI ^® Emerging Markets Index ^SM (the “MSCI Index”) is a stock index calculated, published and disseminated daily by MSCI, through numerous data vendors, on the MSCI website and in real time on Bloomberg Financial Markets and Reuters Limited. The MSCI Index is a free float adjusted market capitalization index designed to measure equity market performance in the global emerging markets and is one of the MSCI Global Investable Market Indices.

As of September 29, 2017, the constituents of the MSCI Index were derived from the constituents of MSCI’s standard single country indexes representing 24 emerging market countries. The five largest emerging market countries included and their relative weightings as of September 29, 2017 are: China (29.55%), South Korea (14.97%), Taiwan (11.51%), India (8.41%) and Brazil (7.56%). Other countries account for 28.01% of the MSCI Index and include Brazil, Chile, China, Colombia, Czech Republic, Egypt, Greece, Hungary, India, Indonesia, Korea, Malaysia, Mexico, Pakistan, Peru, Philippines, Poland, Russia, Qatar, South Africa, Taiwan, Thailand, Turkey and United Arab Emirates.

As of September 29, 2017, the companies included in the MSCI Index were divided into ten global industry classification Sectors, each having a relative weight within the MSCI Index as follows: Information Technology (27.59%), Financials (23.4%), Consumer Discretionary (10.29%), Materials (7.22%), Energy (6.79%), Consumer Staples (6.48), Industrials (5.4%), Telecommunication Services (5.09%), Real Estate (2.88%), Utilities (2.57%) and Health Care (2.28%).

The MSCI Index is considered a “standard” index, which means it consists of all eligible large-capitalization and mid-capitalization stocks, as determined by MSCI, in the relevant market. The MSCI Index has a base date of December 31, 1987.

Information from outside sources is not incorporated by reference in, and should not be considered part of, this document or any accompanying prospectus. UBS has not conducted any independent review or due diligence of any publicly available information with respect to the MSCI ^® Emerging Markets Index ^SM .

Historical Information

The following table sets forth the quarterly high and low closing levels for the MSCI ^® Emerging Markets Index ^SM , based on the daily closing levels as reported by Bloomberg Professional ^® service (“Bloomberg”), without independent verification. UBS has not conducted any independent review or due diligence of publicly available information obtained from Bloomberg. The closing level of the MSCI ^® Emerging Markets Index ^SM on October 17, 2017 was 1,125.66 (the “hypothetical initial level” for the MSCI ^® Emerging Markets Index ^SM ). The actual initial level will be the closing level of the MSCI ^® Emerging Markets Index ^SM on the trade date. Past performance of the MSCI ^® Emerging Markets Index ^SM is not indicative of the future performance of the MSCI ^® Emerging Markets Index ^SM .

The graph below illustrates the performance of the MSCI ^® Emerging Markets Index ^SM from January 3, 2007 through October 17, 2017, based on information from Bloomberg. The dotted line represents the hypothetical downside threshold and the hypothetical coupon barrier of 787.96, which is equal to 70% of the hypothetical initial level. The actual downside threshold and coupon barrier will be determined on the trade date. Past performance of the MSCI ^® Emerging Markets Index ^SM is not indicative of the future performance of the MSCI ^® Emerging Markets Index ^SM .

EURO STOXX 50 ^® Index

We have derived all information regarding the EURO STOXX 50 ^® Index contained in this document, including without limitation, its make-up, method of calculation and changes in its components from publicly available information. Such information reflects the policies of, and is subject to change by STOXX Limited, (the “index sponsor” of the EURO STOXX 50 ^® Index).

STOXX Limited has no obligation to continue to publish the EURO STOXX 50 ^® Index, and may discontinue publication of the EURO STOXX 50 ^® Index at any time. The EURO STOXX 50 ^® Index is determined, comprised and calculated by STOXX Limited without regard to the Notes.

The EURO STOXX 50 ^® Index covers 50 stocks of market sector leaders mainly from 11 Eurozone countries: Austria, Belgium, Finland, France, Germany, Ireland, Italy, Luxembourg, the Netherlands, Portugal and Spain. The EURO STOXX 50 ^® Index captures a selection of the largest stocks among the 19 EURO STOXX regional Supersector indices. The largest stocks within those indices are added to the selection list until coverage is approximately 60% of the free float market capitalization of the corresponding EURO STOXX Total Market Index (the “EURO STOXX TMI”) Supersector Index and from that selection list the 50 stocks are selected. The EURO STOXX 50 ^® Index universe is defined as all components of the 19 EURO STOXX Regional Supersector indices. The EURO STOXX Supersector indices represent the Eurozone portion of the STOXX 600 Supersector indices, which contain the 600 largest stocks traded on the major exchanges of 18 European countries. Each component’s weight is capped at 10% of the EURO STOXX 50 ^® Index’s total free-float market capitalization.

Information from outside sources is not incorporated by reference in, and should not be considered part of, this document or any accompanying prospectus. UBS has not conducted any independent review or due diligence of any publicly available information with respect to the EURO STOXX 50 ^® Index.

Historical Information

The following table sets forth the quarterly high and low closing levels for the EURO STOXX 50 ^® Index, based on the daily closing levels as reported by Bloomberg, without independent verification. UBS has not conducted any independent review or due diligence of publicly available information obtained from Bloomberg. The closing level of the EURO STOXX 50 ^® Index on October 17, 2017 was 3,607.77 (the “hypothetical initial level” for the EURO STOXX 50 ^® Index). The actual initial level will be the closing level of the EURO STOXX 50 ^® Index on the trade date. Past performance of the EURO STOXX 50 ^® Index is not indicative of the future performance of the EURO STOXX 50 ^® Index.

The graph below illustrates the performance of the EURO STOXX 50 ^® Index from January 3, 2007 through October 17, 2017, based on information from Bloomberg. The dotted line represents the hypothetical downside threshold and the hypothetical coupon barrier of 2,525.44, which is equal to 70% of the hypothetical initial level. The actual downside threshold and coupon barrier will be determined on the trade date. Past performance of the EURO STOXX 50 ^® Index is not indicative of the future performance of the EURO STOXX 50 ^® Index.

The graph below illustrates the daily performance of the MSCI ^® Emerging Markets Index ^SM and the EURO STOXX 50 ^® Index from January 3, 2007 through October 17, 2017. For comparison purposes, each underlying asset has been normalized to have a closing level of 100 on January 3, 2007 by dividing the closing level of that underlying asset on each trading day by the closing level of that underlying asset on January 3, 2007 and multiplying by 100. We obtained the closing levels used to determine the normalized closing levels set forth below from Bloomberg, without independent verification.

The closer the relationship of the daily returns of the underlying assets over a given period, the more positively correlated those underlying assets are. The lower (or more negative) the correlation among the underlying assets, the less likely it is that those underlying assets will move in the same direction and therefore, the greater the potential for one of those underlying assets to close below its coupon barrier or downside threshold on an observation date or on the final valuation date, respectively. This is because the less positively correlated the underlying assets are, the greater the likelihood that at least one of the underlying assets will decrease in value. However, even if the underlying assets have a higher positive correlation, one or more of the underlying assets might close below its coupon barrier or downside threshold on an observation date or the final valuation date, respectively, as the underlying assets may decrease in value together. Although the correlation of the underlying assets’ performance may change over the term of the Notes, the correlations referenced in setting the terms of the Notes are calculated using UBS’ internal models at the time when the terms of the Notes are set and are not derived from the daily returns of the underlying assets over the period set forth below. A higher contingent coupon rate is generally associated with lower correlation of the underlying assets, which reflects a greater potential for missed contingent coupons and for a loss on your investment at maturity. See “Key Risks — A higher contingent coupon rate or lower downside thresholds or coupon barriers may reflect greater expected volatility of each underlying asset, and greater expected volatility generally indicates an increased risk of loss at maturity”, “— You are exposed to the market risk of each underlying asset” and “— Because the Notes are linked to the least performing underlying asset, you are exposed to a greater risk of no contingent coupons and losing a significant portion or all of your initial investment at maturity than if the Notes were linked to fewer underlying assets” herein.

Past performance of the underlying assets is not indicative of the future performance of the underlying assets.

The United States federal income tax consequences of your investment in the Notes are uncertain. Some of these tax consequences are summarized below, but we urge you to read the more detailed discussion in “Supplemental U.S. Tax Considerations” of the TACYN product supplement and to discuss the tax consequences of your particular situation with your tax advisor.

U.S. Tax Treatment. Pursuant to the terms of the Notes, UBS and you agree, in the absence of an administrative or judicial ruling to the contrary, to characterize the Notes as a pre-paid derivative contract with respect to the underlying assets. If your Notes are so treated, any contingent coupon that is paid by UBS (including on the maturity date or upon an automatic call) should be included in your income as ordinary income in accordance with your regular method of accounting for U.S. federal income tax purposes.

In addition, excluding amounts attributable to any contingent coupon, you should generally recognize capital gain or loss upon the sale, exchange, automatic call, or redemption on maturity of your Notes in an amount equal to the difference between the amount you receive at such time (other than amounts or proceeds attributable to a contingent coupon or any amount attributable to any accrued but unpaid contingent coupon) and the amount you paid for your Notes. Such gain or loss should generally be long-term capital gain or loss if you have held your Notes for more than one year (otherwise such gain or loss would be short-term capital gain or loss if held for one year or less). The deductibility of capital losses is subject to limitations. Although uncertain, it is possible that proceeds received from the sale or exchange of your Notes prior to a coupon observation date, but that could be attributed to an expected contingent coupon, could be treated as ordinary income. You should consult your tax advisor regarding this risk.

In the opinion of our counsel, Cadwalader, Wickersham & Taft LLP, it would be reasonable to treat your Notes in the manner described above. However, because there is no authority that specifically addresses the tax treatment of the Notes, it is possible that your Notes could alternatively be treated for tax purposes as a single contingent payment debt instrument, or pursuant to some other characterization, such that the timing and character of your income from the Notes could differ materially from the treatment described above, as described further under “Supplemental U.S. Tax Considerations — Alternative Treatments” of the TACYN product supplement, as described in such product supplement. The risk that the Notes may be recharacterized for United States federal income tax purposes as instruments giving rise to current ordinary income (possibly in excess of any contingent coupon and even before receipt of any cash) and short-term capital gain or loss (even if held for more than one year), is higher than with other index-linked securities that do not guarantee full repayment of principal.

Notice 2008-2. In addition, in 2007 the U.S. Treasury Department and the Internal Revenue Service (“IRS”) released a notice requesting comments on the U.S. federal income tax treatment of “prepaid forward contracts” and similar instruments, which might include the Notes. Notice 2008-2 focuses in particular on whether to require holders of these instruments to accrue income over the term of their investment. It also asks for comments on a number of related topics, including the character of income or loss with respect to these instruments and the relevance of factors such as the nature of the underlying property to which the instruments are linked. While the notice requests comments on appropriate transition rules and effective dates, any U.S. Treasury Department regulations or other guidance promulgated after consideration of these issues could materially and adversely affect the tax consequences of an investment in the Notes, possibly with retroactive effect. You should consult your tax advisor regarding the U.S. federal income tax consequences of an investment in the Notes, including possible alternative treatments and the issues presented by this notice. Non-US holders should consult their tax advisors regarding the U.S. federal income tax consequences of investing in the Notes, including the possible application of 30% U.S. withholding tax in respect to the contingent coupons.

Section 1297. We will not attempt to ascertain whether any underlying asset issuer would be treated as a passive foreign investment company (“PFIC”) within the meaning of Section 1297 of the Internal Revenue Code of 1986, as amended (the “Code”). If any such entity were so treated, certain adverse U.S. federal income tax consequences might apply upon the sale, exchange, automatic call, redemption or maturity of a Note. You should refer to information filed with the SEC or the equivalent governmental authority by such entities and consult your tax advisor regarding the possible consequences to you if any such entity is or becomes a PFIC.

Medicare Tax on Net Investment Income . U.S. holders that are individuals, estates, and certain trusts are subject to an additional 3.8% tax on all or a portion of their “net investment income,” which may include any income or gain realized with respect to the Notes, to the extent of their net investment income that when added to their other modified adjusted gross income, exceeds $200,000 for an unmarried individual, $250,000 for a married taxpayer filing a joint return (or a surviving spouse), or $125,000 for a married individual filing a separate return. The 3.8% Medicare tax is determined in a different manner than the income tax. U.S. holders should consult their tax advisors with respect to their consequences with respect to the 3.8% Medicare tax.

Specified Foreign Financial Assets. Certain U.S. holders that own “specified foreign financial assets” in excess of an applicable threshold may be subject to reporting obligations with respect to such assets with their tax returns, especially if such assets are held outside the custody of a U.S. financial institution. You are urged to consult your tax advisor as to the application of this legislation to your ownership of the Notes.

Non-U.S. Holders. The U.S. federal income tax treatment of the contingent coupons is unclear. Subject to Section 871(m) of the Code and FATCA, as discussed below, our counsel of the opinion that contingent coupons paid to a non-U.S. holder that provides us (and/or the applicable withholding agent) with a fully completed and validly executed applicable IRS Form W-8 should not be subject to U.S. withholding tax and we do not intend to withhold any tax on contingent coupons. However, it is possible that the IRS could assert that such payments are subject to U.S. withholding tax, or that another withholding agent may otherwise determine that withholding is required, in which case the other withholding agent may withhold up to 30% on such payments (subject to reduction or elimination of such withholding tax pursuant to an applicable income tax treaty). We will not pay any additional amounts in respect of such withholding. Subject to Section 897 and Section 871(m) of the Code, discussed below, gain from the sale, exchange, automatic call, redemption or maturity of a Note generally should not be subject to U.S. tax unless such gain is effectively connected with a trade or business conducted by the non-U.S. holder in the U.S. or unless the non-U.S. holder is a non-resident alien individual and is present in the U.S. for 183 days or more during the taxable year of such sale, exchange or settlement and certain other conditions are satisfied, or has certain other present or former connections with the U.S.

Section 897 . We will not attempt to ascertain whether any underlying constituent issuers would be treated as a “United States real property holding corporation” (“USRPHC”) within the meaning of Section 897 of the Code. We also have not attempted to determine whether the Notes should be treated as “United States real property interests” as defined in Section 897 of the Code. If an underlying asset issuer and the Notes were so treated, certain adverse U.S. federal income tax consequences could possibly apply, including subjecting any gain to a non-U.S. holder in respect of a Note

upon a sale, exchange, automatic call or other taxable disposition of the Note to the U.S. federal income tax on a net basis, and the proceeds from such a taxable disposition to a 15% withholding tax. Non-U.S. holders should consult their tax advisors regarding the potential treatment of the underlying asset issuer for their Notes as a USRPHC and the Notes as United States real property interests.

Section 871(m) . A 30% withholding tax (which may be reduced by an applicable income tax treaty) is imposed under Section 871(m) of the Code on certain “dividend equivalents” paid or deemed paid to a non-U.S. holder with respect to a “specified equity-linked instrument” that references one or more dividend-paying U.S. equity securities or indices containing U.S. equity securities.  The withholding tax can apply even if the instrument does not provide for payments that reference dividends.  Treasury regulations provide that the withholding tax applies to all dividend equivalents paid or deemed paid on specified equity-linked instruments that have a delta of one (“delta one specified equity-linked instruments”) issued after 2016 and to all dividend equivalents paid or deemed paid on all other specified equity-linked instruments issued after 2018.

Based on our determination that the Notes are not “delta-one” with respect to any underlying asset or any U.S. underlying equity constituent, our counsel is of the opinion that the Notes should not be delta one specified equity-linked instruments and thus should not be subject to withholding on dividend equivalents. Our determination is not binding on the IRS, and the IRS may disagree with this determination. Furthermore, the application of Section 871(m) of the Code will depend on our determinations made upon issuance of the Notes. If withholding is required, we will not make payments of any additional amounts.

Nevertheless, after issuance, it is possible that your Notes could be deemed to be reissued for tax purposes upon the occurrence of certain events affecting the underlying assets, underlying equity constituents or your Notes, and following such occurrence your Notes could be treated as delta one specified equity-linked instruments that are subject to withholding on dividend equivalents. It is also possible that withholding tax or other tax under Section 871(m) of the Code could apply to the Notes under these rules if a non-U.S. holder enters, or has entered, into certain other transactions in respect of the underlying assets, underlying equity constituents or the Notes. A non-U.S. holder that enters, or has entered, into other transactions in respect of the underlying assets, underlying equity constituents or the Notes should consult its tax advisor regarding the application of Section 871(m) of the Code to its Notes in the context of its other transactions.

Because of the uncertainty regarding the application of the 30% withholding tax on dividend equivalents to the Notes, you are urged to consult your tax advisor regarding the potential application of Section 871(m) of the Code and the 30% withholding tax to an investment in the Notes.

Foreign Account Tax Compliance Act. The Foreign Account Tax Compliance Act (“FATCA”) was enacted on March 18, 2010, and imposes a 30% U.S. withholding tax on “withholdable payments” (i.e., certain U.S.-source payments, including interest (and OID), dividends, other fixed or determinable annual or periodical gain, profits, and income, and on the gross proceeds from a disposition of property of a type which can produce U.S.-source interest or dividends) and “passthru payments” (i.e., certain payments attributable to withholdable payments) made to certain foreign financial institutions (and certain of their affiliates) unless the payee foreign financial institution agrees (or is required), among other things, to disclose the identity of any U.S. individual with an account of the institution (or the relevant affiliate) and to annually report certain information about such account. FATCA also requires withholding agents making withholdable payments to certain foreign entities that do not disclose the name, address, and taxpayer identification number of any substantial U.S. owners (or do not certify that they do not have any substantial United States owners) to withhold tax at a rate of 30%. Under certain circumstances, a holder may be eligible for refunds or credits of such taxes.

Pursuant to final and temporary Treasury regulations and other IRS guidance, the withholding and reporting requirements under FATCA will generally apply to certain “withholdable payments” made on or after July 1, 2014, certain gross proceeds on a sale or disposition occurring after December 31, 2018, and certain foreign passthru payments made after December 31, 2018 (or, if later, the date that final regulations defining the term “foreign passthru payment” are published). If withholding is required, we (or the applicable paying agent) will not be required to pay additional amounts with respect to the amounts so withheld. Foreign financial institutions and non-financial foreign entities located in jurisdictions that have an intergovernmental agreement with the United States governing FATCA may be subject to different rules.

Investors should consult their own advisors about the application of FATCA, in particular if they may be classified as financial institutions (or if they hold their Notes through a foreign entity) under the FATCA rules.

Proposed Legislation. In 2007, legislation was introduced in Congress that, if enacted, would have required holders of Notes purchased after the bill was enacted to accrue interest income over the term of the Notes despite the fact that there may be no interest payments over the entire term of the Notes. It is not possible to predict whether a similar or identical bill will be enacted in the future, or whether any such bill would affect the tax treatment of your Notes.

Furthermore, in 2013, the House Ways and Means Committee released in draft form certain proposed legislation relating to financial instruments. If enacted, the effect of this legislation generally would have been to require instruments such as the Notes to be marked to market on an annual basis with all gains and losses to be treated as ordinary, subject to certain exceptions. You are urged to consult your tax advisor regarding the draft legislation and its possible impact on you.

Prospective purchasers of the Notes are urged to consult their tax advisors concerning the application of U.S. federal income tax laws to their particular situations, as well as any tax consequences of the purchase, beneficial ownership and disposition of the Notes arising under the laws of any state, local, non-U.S. or other taxing jurisdiction (including those of the jurisdictions of the underlying constituent issuers).