Inputs - a team's ranks in each of the scored events, and a critical value between 0 and 1. Multiply the team score by the critical value to get the target value. Subtract the largest rank from the target value, and repeat this with the next largest value, etc. until doing so would bring the value below zero. Take the remainder and divide it by the next largest rank, and add the result to the number of subtractions made. Divide this value by the maximum possible value for this, which is the critical value multiplied by the number of scored events, to get the final statistic
I've attached a spreadsheet that calculates the statistic, in case anyone wants to use it/cares. It can be fairly easily replicated in most programming languages (I made an attempt with Java).
Generally, values for the weakest teams tend to range around 0.9 or so, since they're basically just finishing low in most or all of the events. Generally, I would consider anything under 0.4 or 0.35 to indicate significant event bombs. The lowest value that I found was around 0.15, for Piedmont IB Middle School at the NC State Tournament last year.
I have no idea what one would use this statistic for, but I found it interesting so I thought I would share it
