Ohio's unemployment rate dropped by four-tenths of a percent in March to the lowest level in six years.The Ohio Department of Job and Family Services says the seasonally adjusted rate for March is 6.1 percent, which is the state's lowest since April 2008. The national rate is 6.7 percent. 353 thousand Ohioans were out of work last month, down by 24 thousand from February. The department says non-farm payrolls rose by 600 to nearly 5.3 million.