The Yuan's nominal effective exchange rate (NEER), as compiled by BIS, has fallen 4.3 percent since last June, when the Chinese currency was unshackled from a de facto peg against the dollar.
The Yuan has gained 4.5 percent against the US currency over that time, but dollar weakness has meant that the Chinese currency has continued to weaken against those of major trading partners, including the euro, making its imports more expensive.
The Yuan's real effective exchange rate (REER), adjusted for inflation, fell 2.6 percent in March from February, according to BIS, showing that even with Chinese inflation running at more than 5 percent, the Yuan is not becoming dear on a broad basis in real terms.
Chinese officials have increasingly said they are willing to use the Yuan to combat inflation, which the government has made its main task this year.
Central bank chief Zhou Xiaochuan said at the Boao Forum for Asia on Saturday that the Yuan would be one tool the People's Bank of China would use to fend off inflation, potentially meaning appreciation could pick up.
The Yuan has gained 0.9 percent against the dollar so far this year, but with the dollar down over 5 percent over the same period against a basket of currencies, the Yuan has so far continued to decline on trade-weighted terms.