(Bloomberg) -- Chicago’s pension burden climbed last year after the city’s retirement funds lost money due to volatile markets, deepening the long-standing fiscal woes for new Mayor Brandon Johnson.Most Read from BloombergChina Restricts Export of Chipmaking Metals in Clash With USRussian General Still Missing as Defense Chief Slams MutinyLazard Fires Senior Banker for Inappropriate Behavior at PartyBank of America Says it Started Talks With Fed After Stress Test ResultsMusk, Zuckerberg Lead a $