Although the benchmark 225-issue Nikkei average is struggling to get back to the 12,000 level, Tokyo stocks are hardly weak these days.

After falling to a low of 9,420.85 on Feb. 6, a level unseen since Dec. 14, 1983, the Tokyo market raised its upside to 11,919 in March and 11,979 in May.

Even the downside is rising.