Exactly how many runners did I pass?

In my last post where I recapped my 2015 Shamrock Shuffle race, I mentioned that I passed "tons of runners" over the last couple of miles of the race. I thought it would be cool if I could actually quantify how many runners I passed (and how many passed me) from the 5k mark to the finish line (8k mark) of the race. Luckily, the individual results show each runner's time at the 5k mark and their finish time. So, after painstakingly looking at over 300 runners who finished around my time, I have the results of my analysis:

Shamrock Shuffle 2015:
Number of runners I passed after 5k mark:			106
Number of runners who passed me after the 5k mark:			0
My place at 5k mark:			516
My place at the finish line (8k):			410

So my "tons of runners" translates to 106 runners passed in just over over 11 minutes - about 10 per minute. I went way down the list to see if anyone had passed me over the same stretch and could not find a single person. This info shows just how big a negative split I ran. However in the long run, the only time that matters is the one that displayed as I crossed the finish line. Lots of other runners who went out a lot faster than me then slowed down more than me, still beat me. Bottom line: While it's fun to pass other runners, you can still get beat by lots of faster "positive splitters" and "even pacers".

Anyway, I also saw that someone on reddit had downloaded the stats of every finisher of the 2014 Chicago Marathon into an Excel spreadsheet. So, using that data, I did the same analysis as above, except this time I calculated the number of runners I passed and was passed by after the halfway (13.1 mile) mark:

Chicago Marathon 2014:
Number of runners I passed after 13.1 mile mark:			481
Number of runners who passed me after the 13.1 mark:			117
My place at 13.1 mile mark:			2,127
My place at the finish line (26.2 miles):			1,763

The interesting thing with this is that I was down on myself for my "big" positive split during the Chicago Marathon, but I needn't really be. Of the runners who passed the half way mark at 1:32:52 or faster, I finished with a faster time than 481 of them. Only 117 runners who ran slower than me for the first half, had a faster time than me. That means that my positive split actually was decent when compared to how big other runners' positive splits were. I shouldn't get down on myself too much - I ran faster than most for the second half! Anyway, next year I hope to be one of those 117, which means starting even slower and finishing even faster!

2014 Chicago Marathon Finish

Next up: Ravenswood Run in 11 days!