The benefits of defined benefit and defined contribution plans differ based on the degree of financial security provided to the retiree. With defined benefit plans, retirees receive a guaranteed payout at retirement, determined by a fixed formula based on factors such as salary and years of service.[8] The risk and responsibility of ensuring sufficient funding through retirement is borne by the employer or plan managers. This type of plan provides a level of financial security for retirees, ensuring they will receive a specific amount of income throughout their retirement years. However this income is not usually guaranteed to keep up with inflation, so its purchasing power may decline over the years.