The Central Time Zone includes the states of Alabama, Arkansas, Florida, Illinois, part of Indiana, Iowa, part of Kansas, part of Kentucky, Louisiana, part of Michigan, Minnesota, Mississippi, Missouri, Nebraska, North Dakota, Oklahoma, part of South Dakota, part of Tennessee, most of Texas, and Wisconsin.
(Total non work time) 30 days. Total days available for work 230 days. Next you have to determine your actual billable time. In most settings, the actual billable time will average 6 hours out of every 8, due to cancellations, no shows, or other problems. So: Available time = 230 days =1840 hrs/yr. Billable time/day = 6/8 =1380 hrs/yr.
In 1840, the average employee worked for 13 hours a day, six days a week. Fortunately, the 40-hour, 8-hours-per-day workweek has become the standard in many occupations, and is generally accepted as the norm. However, salaried employees' workweeks need not hold to this standard.