Month to month comparisons like the one I publish at the beginning of the month for the previous month are actually an average for the entire month, not the low figure for the month. The yearly ice curve I sometimes post (the colorful one that looks like a crazy sine wave) is a five day rolling average.

I once wrote an X-ray diffraction data analysis program that had a user-controllable variable averaging window size with user-adjustable weighting for each observation within a window. It used some new statistics I "invented", like the mean deviation from the mean, the median deviation from the mean, the mean deviation from the median, and the median deviation from the median. The crystallographer I was working for loved fiddling with these buttons.

You could do stuff like that with Fortran.