Abstract: A method for analyzing a drilling operation includes obtaining a first set of logged operational data from the drilling operation through a first time interval, obtaining a set of operational activity dividers that delimit second time intervals within the first time interval, allocating one of a plurality of pre-defined activities to each of the second time intervals, wherein a first activity is one of the plurality of pre-defined activities, calculating a first performance indicator parameter for the second time intervals which have been allocated to the first activity, generating a time-dependent profile of the first performance indicator parameter for the second time intervals, and outputting at least one calculated value of the first performance indicator parameter to an operator. The first performance indicator parameter is calculated as a function of a duration of a respective second time interval which has been allocated to the first activity.