The paper calculates the FH index (Feenstra & Hanson, 1996 & 1999) for 33 manufacturing industries to measure Chinese off-shoring, using three annual input/output tables in 1997(124 industries), 2002(122 industries) and 2007(135 industries) constructed by the Bureau of National Statistics. Compared to our calculation for 19 industries and the past researches based on 42 sector input/output tables, the results show great distinct variation trend on service off-shoring after adding data of the year 2007, suggesting that different industry classification may lead to the misjudgment on real off-shoring level. Although off-shoring calculating is subject to data bottleneck, the rational treatment on the data and appropriate adjustment to existing methods could greatly help us get closer to the truth.