Offshore yuan strengthened sharply on Monday ahead of the decision, with the currency rising 0.4 percent against the US dollar during the trading, marking the biggest gain in a month.

In a muted reaction to the inclusion news, the central parity rate of the yuan weakened on Tuesday by 11 basis points to 6.3973 against the US dollar, according to the China Foreign Exchange Trading System.

"Expectations have already been riding high that the board would formally announce the RMB's inclusion, which implies that a lot of near-term expectations should already be factored into the RMB movement," HSBC said.

The market reached a consensus that immediate yuan demand triggered by the new formula will be negligible due to the limited asset value of total SDR outstanding.

Over the long run, the balance of risk remains tilted toward depreciation, a latest Bloomberg Brief special report commented on the issue.

Membership in the IMF's SDR club might encourage more funds to flow into China, but the capital-account opening that SDR inclusion is intended to catalyze may see even larger quantities of funds flowing out, the report said.

It projected a median forecast for the yuan to end 2015 at 6.4 against the dollar and drop further to 6.6 at the end of 2016.

Wang Tao, a UBS economist, expects a 5 percent depreciation of the yuan against the US dollar in 2016 in a gradual rather than one-off manner.

The Aug 11 depreciation move, explained by the PBOC as allowing the central parity rate of the yuan to better reflect the market rate, was largely understood by the market as China wishes to have a solid grip on fairly stable exchange rate while maintaining independence on making monetary policies.

While the immediate benefits of the yuan's SDR entry may be limited, economists have looked beyond the symbolic significance of the label to far-reaching implications for China's economic and financial reforms.

"The significance will continue to lie in all the necessary financial reforms and the capital-account opening to achieve a positive outcome and further advance RMB internationalization," Wang said.

Following the IMF decision, China's central bank vowed to speed financial reforms and opening up to make positive contribution to global economic growth, financial stability and economic governance.