Pizza Girl: Statistical Analysis of a Delivery Shift: Part 1


Another important use of pizza: learning fractions and percentages. [Photograph: Pizza Girl]

How much time do I really spend driving during any given shift? How much time do I spend folding boxes? What is my average hourly rate per shift? On a delivery by delivery basis? How much better is it to take a triple instead of a double delivery? How much does a zero tip affect my effective hourly rate?

I often have questions like this, and the best way I could think of answering them was to track my every movement during a shift, so for three peak shifts (Friday or Saturday night) I recorded everything I was doing, from my clock-out time to the time I spent folding boxes (sometimes I feel like I do nothing but fold boxes, though as you'll see, the data says otherwise). Over the next few weeks I'm going to take that data and see what sort of useful information I can pull from it.

Here's an example of my raw data (you can view the full raw data here):

5:28: arrive
5:31: clock in
5:33–5:45: fold boxes (12 minutes)
5:45–5:48: work ovens (3 minutes)
5:48: routed
5:50: leave on delivery (11 minutes travel time)
6:01: arrive at delivery ($3 tip)
6:01: leave house (11 minutes travel time)
6:12: Arrive at store (24 minutes run time for 1 delivery)
6:12–6:15: work ovens (3 minutes)
6:15: routed
6:18: leave on delivery (15 minutes travel time)
6:33: arrive at house ($3 tip)
6:35: leave house (3 minutes travel time)
6:38: arrive at second delivery ($2 tip)
6:38: leave house (14 minutes travel time)
6:52: arrive at store (37 minutes run time on two deliveries)
6:52–7:02: work ovens (10 minutes)

I took that data and went crazy with a spreadsheet to figure out both the percentage of time I spent doing various tasks as well as the average hourly rate I made on each delivery as well as on the shift as a whole.

Before I start analyzing I want to give a few caveats:

  • A few of the times are estimates. I would probably get yelled at a bit if I was pulling out my phone every time they asked me to come work the ovens so that I could record the time. I did however try to check the time and remember it for when I could record it.
  • For hourly wage estimates I'm excluding the $1.29 per delivery gas/maintenance reimbursement that I get.
  • Just to be clear, I get $7.50/hr while not clocked out on a run and $4.95/hr while I am clocked out on a run.
  • These results are likely to be significantly different for weeknight shifts and drivers who are on a different pay-scheme than I am. It's also a very limited data-set, so it may not be completely representative of typical shifts (though they certainly felt typical.
  • I consider a shift to be successful if I make at least $12.50 an hour. I chose this number because it is what I made at my primary job when I started delivering pizza and, since I couldn't get extra hours there, a second job would be worth my time if I could net the same wage. I've shopped it around with a few other delivery people and the consensus seems to me that it's a reasonable goal (when excluding gas reimbursement).
  • I'm not a statistician. I took a class in college for statistics, but that's about it, and I mostly learned that data can be made to say whatever you want. I'm definitely open to improving my method if you find that I'm doing something wrong or that I'm not taking into account some variable is completely skewing my results.

Next week I'll go into more of a breakdown of each shift (and have a neat pie chart!), but in the meantime, to answer the first question I posed, "How much time do I really spend driving during any given shift?":

Over three shifts I spent 67% of my shift driving.