In a pleasant surprise, the wholesale price index (WPI), India's main inflation gauge, unexpectedly eased to 6.62% for the month of January as compared to 7.18% (Provisional) for the previous month and 7.23% during the corresponding month of the previous year. Build up inflation in the financial year so far was 5.09% compared to a build-up of 6.15% in the corresponding period of the previous year.