On ships they sound the tanks daily (water, oil, fuel) and use the depths to calculate the volumes. There are dozens of tanks. Part of my job was then to use t

On ships they sound the tanks daily (water, oil, fuel) and use the depths to calculate the volumes. There are dozens of tanks. Part of my job was then to use that data to figure out the change in the ship's draft from day to day. Which could be done two ways: drawing lines on Xerox copies of an odd set of nomograms, or brute calculation. I found the nomograms fraught with opportunities for error. Luckily the oil king responsible for the soundings kept them in Excel. So I wrote a sheet that took his data and did all the brute force calculations. So when he printed the daily soundings, instead of handing them to me, the draft report just printed out as the next page. It was more accurate and saved me 1-2 hours a day. And looked nice and crisp coming off the laser printer. Everyone thought I was a magician. The guy who took over for me had a nervous breakdown.