Column B is the day of the week. Column C is the sales for that day.
Current formula is: =SUMIF(B3:B367;"=Monday";C3:C367).
With or without the = the sum provided is $0.00. If it matters.. The cells are formatted as $1,234.56
Example Data Entered - Wednesday $120.00
Sum Shows:
Sunday $0.00 Monday $0.00 Tuesday $0.00 Wednesday $0.00 Thursday $0.00 Friday $0.00 Saturday $0.00 Total $0.00