Can I, somehow, based on time stamp and how much is done, estimate time and date for when a job is complete? I got this log that a bot I've made writes in column A time [yyy-mm-dd hh:mm], and in column B it wrights how much is done. It sorts it all with newest on top.
Gary's answer is correct, but for convenience if the 2nd row of data can be an arbitrary progress status (not just start of task = implicitly 0%), and if you use percentage number format (or decimals) and you would like to get the end date instead of just the duration, use following formula:
=A1+(A1-A2)/(B1-B2)*(1-B1)