I am creating a spreadsheet that will record weight gained/lost and I have
the basic spreadsheet done.

However, I need to have a cell that returns a value equal to the difference
between the starting weight and the most recent weight - which is not
necessarily the lowest weight, so I can't use MIN()

Values are being added every few days and as such Excel needs to update as
needed each time. All weight data is entered within the same column.

Has anyone got any advice please.

Thanks.