Spring break is upon us. Many students of mine are heading to exotic location, and quite a few of them have reserved rental cars many weeks earlier. But here is the question: When do most people make rental reservations? A week in advance? Or, just a few days in advance?

I have worked with a rental car company, which gave us some reservation data. With that, my students are I went to work. And our tool of choice? Excel PivotTable.

The first thing to calculate is the advance amount, which is simply

Advance = Pickup date – Reservation date

Then we use PivotTable to draw a histogram (See here for a video demonstration on how to efficiently draw histograms with PivotTables).  The result is as follows:

It turns out there were 29% reservations that were made 1 day prior or even less!  There were 17% reservations made 2-3 days prior.  Adding these two together there are 46% reservations that were made 3 days prior or less.

There were people who made reservation as far advance as 4 months earlier, but those are rare cases.  Overall, almost half of us make reservations less than a week in advance.