Economy watchers are celebrating Monday, over Japan Inc.'s June shift to optimism from pessimism, as seen in the latest tankan survey of business sentiment.

The positive headline number from that survey (a plus 4, up from a minus 8 in March) showed that more big Japanese manufacturers like Toyota Motor Corp. are optimistic about overall business conditions than pessimistic--results that make sense, since many big global manufacturers have seen profits from overseas operations boosted recently by a dramatically weaker yen.

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