Tested with a worksheet with 1.8million rows and 5 columns with a reference column of two categories. The split speed improved from 158 sec in Origin 2020 to 12 sec in Origin 2020b.
More split options when splitting worksheet by Reference column, such as direction change, direction reset, reference value change. E.g. if X value increase, then decrease, and then increase again, user can split worksheet into 3 sheets so each x part is monotonic.
