Solved:

(CASE WHEN YEAR(H.effdt) IN ('2001', '2002') THEN

(CASE H.review_rating

WHEN '1' THEN 'Exceeded Way, Exceeded Results'

WHEN '2' THEN 'Exceeded Way, Achieved Results'

WHEN '3' THEN 'Exceeded Way, Did not meet Results'

WHEN '4' THEN 'Achieved Way, Did not meet Results'

WHEN '5' THEN 'Achieved Way, Achieved Results'

WHEN '6' THEN 'Achieved Way, Exceeded Results'

WHEN '7' THEN 'Did not meet Way, Exceeded Results'

WHEN '8' THEN 'Did not meet Way, Achieved Results'

WHEN '9' THEN 'Did not meet Way, Did not meet Results'

ELSE 'Empty'

END)

WHEN YEAR(H.effdt) IN ('2003','2004','2005') THEN

(CASE H.review_rating

WHEN '1' THEN 'Does not Meet Expectations'

WHEN '2' THEN 'Partially Meets Expectations'

WHEN '3' THEN 'Meets Expectations'

WHEN '4' THEN 'Exceeds Expectations'

WHEN '5' THEN 'Far Exceeds Expectations'

ELSE 'Empty'

END)

END) AS review_rating