中国财政部发行20年期债券，规模500亿元，发行利率1.9909%，预期1.9900%，投标倍数3.02倍，边际倍数1.69倍。

Group 1 - The Ministry of Finance of China issued a 20-year bond with a scale of 50 billion yuan [1] - The issuance interest rate was set at 1.9909%, slightly above the expected rate of 1.9900% [1] - The bid-to-cover ratio was 3.02 times, indicating strong demand for the bond [1] - The marginal bid-to-cover ratio was 1.69 times, reflecting the competitive nature of the bidding process [1]