Capacity building is an ongoing problem experienced by NPOs for a number of reasons. Most rely on external funding (government funds, grants from charitable foundations, direct donations) to maintain their operations and changes in these sources of revenue may influence the reliability or predictability with which the organization can hire and retain staff, sustain facilities, create programs, or maintain tax-exempt status. For example, a university that sells research to for-profit companies may have tax exemption problems. In addition, unreliable funding, long hours and low pay can result in employee retention problems. During 2009, the US government acknowledged this critical need by the inclusion of the Nonprofit Capacity Building Program in the Serve America Act. Further efforts to quantify the scope of the sector and propose policy solutions for community benefit were included in the Nonprofit Sector and Community Solutions Act, proposed during 2010.