Marco Russo and Alberto Ferrari break the ties:
DAX already offered two ranking functions so far: RANK.EQ and RANKX. While RANK.EQ is very seldom used, RANKX has been the primary ranking function for a long time. We wrote several articles about RANKX: one of them deals with ranking on multiple columns, a scenario that requires some DAX acrobatics to be solved as described in RANKX on multiple columns with DAX and Power BI.
The new RANK function makes ranking on multiple columns much easier because it offers sorting by multiple columns as a native feature, because it belongs to the family of window functions. Thanks to the concept of current row in window functions, RANK also helps in a subtle issue with RANKX – which despite being rare, might affect ranking on decimal numbers as described in Use of RANKX with decimal numbers in DAX.
Read on to see how you can use RANK() and how it compares to RANKX().