The head of Switzerland’s financial regulator, the Swiss Financial Market Supervisory Authority (FINMA), is stepping down, citing the stress of the position.

FINMA announced that its CEO, Urban Angehrn, will leave the agency at the end of the month, after less than two years on the job.

During that time, the regulator has coped with the fallout from the shifting economic and financial environment, and a crisis at Credit Suisse, which represented “the biggest challenge in FINMA’s history,” it said in a release.

“Being able to contribute to the sustainable improvement of the quality of the Swiss financial centre as CEO of FINMA was a unique challenge for me, and one that I tackled with all my might. However, the high and permanent stress level had health consequences,” said Angehrn in announcing his decision to resign.

FINMA appointed deputy CEO Birgit Rutishauser as interim CEO, and said it has begun the search for a permanent replacement.

“Urban Angehrn will be at her disposal to ensure an orderly handover of all business and for follow-up to the takeover of Credit Suisse by UBS,” it said.