More Americans are living to 90 and beyond, and by 2050 their ranks could reach almost 9 million, finds the US Census Bureau’s report titled “American Community Survey Reports:  ACS-17, 90+ in the United States: 2006–2008.”   Revealing that the number of nonagenarians has nearly tripled -- from 720,000 in 1980 to 1.9 million in 2010, and by 2050 their ranks could reach almost 9 million. this age group now the fastest-growing group in the older population.  Noting that more older people are living alone, the report warns that they are not necessarily healthy or independent – many live in assisted living facilities or have other home services such as visiting nurses, or help from family.  In fact, the report reveals that 85% of those 90 and older say they have one or more physical limitations, with about 66% have difficulty walking or climbing stairs.