By Neil MacLucas 
 

ZURICH--An index measuring the confidence of Swiss consumers was unchanged in the second quarter, reflecting concern about the strong Swiss franc's impact on the economy, according to a survey released Thursday.

The quarterly Swiss Consumer Sentiment Index was at minus 6, unchanged from the previous quarter. The index is compiled by the State Secretariat for Economic Affairs, known as Seco, and is based on a poll of 1,200 households. Economists expected an average of minus 9.

The survey is the second since the Swiss National Bank's decision to scrap the cap for the franc on Jan. 15.

The government expects the SNB's decision to allow the franc to float freely to weigh on economic growth in the coming years.

The economics department currently forecasts Swiss gross domestic product growth of 0.9% and an average unemployment rate of 3.3% this year. For 2016, GDP growth is expected to strengthen to 1.8% while unemployment rises to 3.4%. It will release new projections on June 16.

Write to Neil MacLucas at neil.maclucas@wsj.com