The Pension Estimator uses the statement date as the point from which it begins estimating future pension accruals.
If you have a recent statement handy, enter the quarter and year reflecting the statement date, and also enter the year-to-date hours as shown on the statement.
If you don't have a recent statement available, enter the 4th quarter of last year as the statement date and zero for year-to-date hours.
Even if you don't have the exact amounts of your previous accruals, the estimator will be able to give you a ball-park estimate based on your approximated accruals.