what is the range of retail prices for a 2-carat round-cut diamond
which has been graded by the GIA as G color, VS1 clarity (and has a
GIA certificate)?

In order of carat, color, clarity, cert, depth, table, flr, sym, pol,
girdle, culet, measurements, and last but not least, the hefty price

2.00 G VS1 GIA 64.8 61.0 strong vgood vgood med-thk none 7.83x7.92x5.1 20679   
2.00 G VS1 GIA 64.8 61.0 strong vgood vgood med-thk none 7.83x7.92x5.1 20866   
2.00 G VS1 GIA 60.2 59.0 med exc vgood thn-med-fc none 8.13x8.18x4.91 21237   
2.00 G VS1 GIA 61.7 56.0 none exc vgood med-fctd none 8.07x8.11x4.99 22235   
2.00 G VS1 GIA 58.7 61.0 none vgood good vthn-med none 8.27x8.31x4.87 22389   
2.00 G VS1 GIA 58.7 61.0 none vgood good vthn-med none 8.27x8.31x4.87 22590   
2.00 G VS1 GIA 62.6 57.0 none good vgood sthk-thk-f small 7.91x7.96x4.97 2789   
2.00 G VS1 GIA 62.2 59.0 none exc vgood med-sthk-f none 8.06x8.03x5.00 23008   
2.00 G VS1 GIA 58.7 61.0 none vgood good med-med none 8.31x8.27x4.87 23600   
2.00 G VS1 GIA 61.0 57.0 faint good good med-thk-fc none 8.11x8.19x4.97 23684   
2.00 G VS1 GIA 59.0 61.0 none good good med-sthk none 8.23x8.32x4.88 23684   
2.00 G VS1 GIA 59.9 59.0 none good vgood med-sthk none 8.15x8.25x4.91 23754   
2.00 G VS1 GIA 59.9 59.0 none good vgood med-sthk none 8.15x8.25x4.91 23968   
2.00 G VS1 GIA 61.0 57.0 faint good good med-thk-fc none 8.11x8.19x4.97 23976   
2.00 G VS1 GIA 60.0 60.0 none vgood vgood med-sthk-f none 8.24x8.18x4.93 4079   
2.00 G VS1 GIA 61.8 65.0 none vgood vgood thn-med-fc none 7.93x8.08x4.9324192   
2.00 G VS1 GIA 62.3 58.0 none exc exc med none 8.06x8.10x5.03 24420   
2.00 G VS1 AGS 62.0 56.0 none ideal ideal med-sthk-f none 8.06x8.14x5.02 4979   
2.00 G VS1 GIA 62.4 54.0 none exc exc med-sthk none 7.96x8.03x4.99 25083   
2.00 G VS1 GIA 62.7 57.0 faint vgood vgood  none 8.03x8.11x5.06 25099 

hope this helps