A formula option;

If B:B contains only numbers,

Code:
=MATCH(1E+100,B:B)
If B:B contains only texts,

Code:
=MATCH(REPT("Z",250),B:B)
If B:B contains numbers & texts,

Code:
=MAX(LOOKUP(1E+100,CHOOSE({1,2},0,MATCH(REPT("Z",250),B:B))),LOOKUP(1E+100,CHOOSE({1,2},0,MATCH(1E+100,B:B))))