It will not show up in time for this week's earnings release, but Toyota Motor Corp. may have gotten a gift from the Bank of Japan's unconventional policy choices.

The central bank's surprise move on Friday to negative interest rates could boost domestic demand, while the weaker currency that is likely to result from the policy is a boon for exporters. This is particularly important to Toyota, which earns more profit than all other Japanese automakers combined.

The maker of Corolla compacts and Prius hybrids, which reports earnings Feb. 5, may earn a record ¥2.39 trillion in the fiscal year ending in March, according to the average estimate of 26 analysts. Foreign exchange effects boosted the company's operating income by ¥305 billion in the first half of its fiscal year.