In August 2012 the Bureau of Labor Statistics released the findings of a supplementary set of questions that had been asked as part of the traditional 2011 American Time Use Survey (ATUS). This survey provides estimates on how people spend their time. The additional leave module was sponsored by the Labor Women's Bureau: it computed data about wages and access to paid leave. It showed a significant number of workers don't have paid leave. How significant?
On average, in 2011, 59 percent of wage and salary workers had access to paid leave, so 41% did not
By occupation, workers in management, business, and financial operations jobs were the most likely to have access to paid leave (77 percent).
Seventy-six percent of workers in the public sector had access to paid leave, compared with 57 percent of private-sector workers.
Among single jobholders, full-time wage and salary workers were more than 3 times as likely to have access to paid leave than were part-time workers. Well paid workers had much more access to paid leave than the low paid workers: 83 percent of full-time wage and salary workers in the highest earnings range had access to paid leave, compared with 50 percent of full-time workers in the lowest earnings ranges.
The clearest report I could find was by Frank Bass in Bloomberg News: About 40 percent of U.S. workers, or more than 55 million Americans, don’t get paid when they take vacation or sick days, the government reported.