A computer-readable recording medium storing therein a report preparation program that causes at least one of storages and a computer coupled to the at least one of storages to execute a process for calculating an individual-feature quantity with respect to an input output per second (IOPS) of the at least one of storages for each piece of time-series data included in a time-series data group with respect to the IOPS; statistically processing the calculated individual-feature quantity of the time-series data group; calculating an entire-feature quantity based on the statistically processing; referring to a learning model generated based on at least one of learning time-series data groups and contents of a report for the at least one of learning time-series data groups, the learning model representing a relationship between an entire-feature quantity and contents of the report; and outputting information on contents of the report corresponding the calculated entire-feature quantity.