The agency says membership in public sector pension plans rose 1.8 per cent to 3,140,970, while the number of members in private sector plans declined 0.5 per cent to 2,924,790.
The public sector accounted for 52 per cent of total membership in registered pensions, up from 46 per cent a decade earlier.
Overall in 2010, 38.8 per cent of all employees were enrolled in registered pensions, down from 39.2 per cent in 2009.
In the private sector, the proportion of employees covered by a plan slipped to 24.4 per cent in 2010 from 24.8 per cent the previous year.
In 2010, 74 per cent of employees in a registered pension were in a defined benefit plan, with 16 per cent covered by defined contribution plans and about 10 per cent in hybrid plans.