Creating a macro for VBA

The services of a macros writing specialist are required. You need to create a macro to process the data array in Excel.
Calculation of the average value (according to the standard formula) of the water temperature for each meter (in one column the depth, like 0, 0.4, 0.6, 1.1, 1.7, 2.5 ...; in another temperature value) and output of the result in a separate table. Macros is needed because of the large amount of data (more than 100 thousand).