I have 20 years' worth of observations that either say YES or NO to the question of whether breeding was observed. I want to present the averages of the YES observations across the years, demonstrating what the average breeding effort looks like across a 20-year period. My issue is that early on a lot fewer observations (n=100) were made compared to present day (n=1000). I believe this might skew the results and result in a graph that is misleading in presenting a genuine trend over the years.
My question is whether I should weight my averages, log transform them or disregard certain data based on confidence intervals?
Any help would be greatly appreciated.
This is what the data looks like at the moment: