SELECT A.BUSINESS_UNIT, A.ASSET_ID, A.BOOK, A.IN_SERVICE_DT,
A.BEGIN_DEPR_DT, A.LIFE,
CASE
WHEN A.LIFE-(COUNT(D.ACCOUNTING_PERIOD)+((C.END_DT-A.BEGIN_DEPR_DT)/
     (C.END_DT-C.BEGIN_DT))-1) < 0 THEN 0
ELSE A.LIFE-(COUNT(D.ACCOUNTING_PERIOD)+((C.END_DT-A.BEGIN_DEPR_DT)/
     (C.END_DT-C.BEGIN_DT))-1)
END AS REMAINING_LIFE
FROM PS_BOOK_CUR_VW A, PS_BU_BOOK_TBL B, PS_CAL_DETP_TBL C,
     PS_CAL_DETP_TBL D, PS_SET_CNTRL_REC T
WHERE A.BUSINESS_UNIT = B.BUSINESS_UNIT
AND A.BOOK = B.BOOK
AND A.BUSINESS_UNIT = T.SETCNTRLVALUE
AND T.REC_GROUP_ID = 'FS_02'
AND T.RECNAME = 'CAL_DETP_TBL'
AND C.SETID = T.SETID
AND B.CAL_DEPR_PD = C.CALENDAR_ID
AND D.SETID = T.SETID
AND B.CAL_DEPR_PD = D.CALENDAR_ID
AND A.BEGIN_DEPR_DT >= C.BEGIN_DT
AND A.BEGIN_DEPR_DT <= C.END_DT
AND D.END_DT >= C.END_DT
AND D.END_DT <= (SELECT DISTINCT N.AS_OF_DATE FROM PS_ASSET_NBV_TBL N
     WHERE N.OPRID = 'VP1' AND N.RUN_ID = 'NBV' AND A.BOOK = N.BOOK)
GROUP BY A.BUSINESS_UNIT, A.ASSET_ID, A.BOOK, A.LIFE, A.IN_SERVICE_DT,
     A.BEGIN_DEPR_DT, C.END_DT, C.BEGIN_DT
ORDER BY A.BUSINESS_UNIT, A.ASSET_ID, A.BOOK;

Note: The SQL hasn't been performance tuned yet.  I will post ways to tune this SQL, or appropriate indexes for the tables referenced, once I have them identified.