Group 1 - The basis for the CSI 300 IF2506 contract is at a discount of 26.34, the SSE 50 IH2506 contract is at a discount of 17.22, the CSI 500 IC2506 contract is at a discount of 51.21, and the CSI 1000 IM2506 contract is at a discount of 69.17 [1] - The month difference for the CSI 300 IF2506-2507 is 39.2, for the SSE 50 IH2506-2507 is 30.2, for the CSI 500 IC2506-2507 is 68.8, and for the CSI 1000 IM2506-2507 is 91.2 [1]