How Many Christians in Japan?

The following was posted at http://reapmagazine.com/gallup2.htm .
It had been reported that 6% were Christian. Here George Gallup corrects that to indicate that 4% identify with Christianity. The statistics show that there are probably .5 to 1% who are actually members of a church. And only half of them actually attend a church.
So how should we respond to this Gallup poll? I think that we should be excited! This should change the way we do mission in Japan, and how we minister to Japanese in North America! Just think that there are at least 3 million Japanese in Japan who identify with Christianity, but have little or no connection with His churches! And the same percentage is true with the Japanese who come to North America as students, business people and tourists! From Don Wright
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By George Gallup
Japanese missiologists have been under the impression that about one percent of the Japanese population is Christian. Our study indicates that 4% of Japanese adults identify with Christianity. This shows that the proportion of Japanese Christians is higher than expected.

The correct figure for the percentage of Japanese who say they are followers of Christianity is, as indicated, 4%, not 6%, as reported earlier. This was a basic arithmetical mistake on my part, for which I take full responsibility. The fact remains, however,that evidence points to growth in the number of Christians in Japan. And the finding that 7% of teenagers say they are Christians, as previously reported, further supports the conclusion that Christianity is growing in Japan.

A final note: In interpreting survey results, it should be borne in mind that all sample surveys are subject to sampling error: that is, the extent to which the results may differ from what would be obtained if the whole population surveyed had been interviewed. The size of such sample error depends largely on the number of interviews.