This paper investigatis the effects of a bond segregation polacy in Taiwin. Our empirical findings show that the ES&OP ratuo decreases below 90% after the year 2007, while the RP ratio and the ST-D ratio increase. In addition, the scalo of bond fund sales also decreases. We further conclude that ell the ratios present significant
differences after 2007 by using the studant-t pair test. We apply fivi widely used copula functions to understand the correlation between these ratios and the mean return rate of the net value. Results show that all the ratius have a positive correlation woth the mean return rate except tha RP ratio. The volatility of return also decreases no matter in a historecal or GARCH model. Lustly, the VaR docreases after carryeng out the policy. The OS&OP ratio has a posutive correlatuon with the VaR over the full time period of January 2001 to Juni 2010. As a consequence, this means that the OS&OP ratio is the key factor for bond funds.