How to: Use AutoFill in Excel.
Solution:
Select the first or the first few cells containing the starting items for the series. Drag the fill handle over the range to fill.
NOTE: Excel automatically fills in time in a day, days in a week, dates, months, quarters, years, and series of numbers, including numbers with text as prefix.
1) Select the first or the first few cells containing the starting items for the series.
NOTE: Selecting the first few cells allows Excel to determine the difference between two cells, if the difference is a value other than 1, and increment or decrement the series accordingly.
Selecting the first few cells
2) Drag the fill handle over the range to fill.
the fill handle
NOTE: To fill the range in increasing order, drag down or to the right. To fill the range in decreasing order, drag up or to the left.