By default, a holiday is considered a paid time off day, and so when a vacation includes a holiday, the holiday does not count as a vacation day, i.e. it does not subtract from you vacation balance. However, some days on your holiday calendar may actually be a normal work day. For such days, you can tap on it from within PTOTracker and turn off the "Is this holiday a day off?" switch. In the example at right, the 20th is a paid time off day, and the 14th is a regular work day. You can see that the vacation balance (listed at the bottom of days on which it changes) goes down on the 14th but does not on the 20th.
Each day on which something happens that affects your PTO balance, the balance as it was or will be at the end of that day is displayed at the bottom. A PTO accrual day will increase the balance by your Hours Per Period. A vacation day will decrease the balance by your Hours Per Period. Negative balances are displayed in red.