Calculating percentage of formats (4k vs HD) in timeline

Hello wonderful Premiere users!

I'm required to calculate the percentage of different formats in a timeline eg. for instance 20% total duration of 4k in the timeline, 70% total duration of HD and 10% total SD content. This is a requirement of international broadcast delivery. AVID has a built-in calculator for this.

In an effort to calculate this from my Premiere timeline, I listed every format in my Google Sheets shot log which shows the in timecode (HH:MM:SS:FF) of every shot. Trying to work out each shot duration was failing because Google Sheets doesn't calculate with Frames. Also trying to use the help of the great custom Timecode formula in Google sheets hasn't helped with this conundrum. (TIMECODE CALCULATOR ON GOOGLE SHEETS: https://docs.google.com/spreadsheets/d/12MUatPWIHteADCKNIafR25Y8DJr2RPB_xdfjYbjWZwo/htmlview

Any thoughts, on if I can use my existing shot log with all the formats listed, or if there is a way to do this in Premiere that would be a life saver! All the best, Jasmine