The biggest spike in pension costs is from 2020 through 2023, when the city’s contributions to the four funds are projected to rise from about $1.3 billion to nearly $2.3 billion a year. The increase begins next year, when payments to the police and fire funds are expected to rise by $281.2 million. For the municipal and laborers funds, payments increase in 2022, when the city will need an additional $370 million a year to cover the tab.