If you allow too much tax to be withheld, you get a refund. You can determine how much is tax is taken out of your pay by the number of allowances you claim on your W-4. The W-4 has a worksheet to help you figure out how many personal allowances to take.
Step 5: Predict your next period. Now that we know how long your period cycle is, we can just use it to count the days to predict your next period. My period cycle is 28 days so if I count 28 days from February 10, that's when my next period should come.
Then they either assume that your periods are exactly 28 days apart or that you ovulate exactly 14 days before your next period. A better way is to use over the counter ovulation prediction kits which will help you know when exactly you are ovulating and time intercourse ...Read more.