For global equity investors and Shinzo Abe, it's splitsville.

Starting in the first days of 2016, foreign traders have been pulling out of Tokyo's stock market for 13 straight weeks, the longest stretch since 1998. Overseas traders dumped $46 billion of shares as economic reports deteriorated, stimulus from the Bank of Japan backfired and the yen's surge pressured exporters. The benchmark Topix index is down 18 percent in 2016, the world's steepest decline behind Italy.

Losing the faith of foreign traders would be a blow to the prime minister — they're the most active in a market Abe has held up as a litmus on his growth strategies.