The LG D2343P has a maximum contrast ratio of 50000000:1. That's over two times the contrast ratio of the most frequently found dynamic contrast ratio of 20000000:1. Across all medium monitors that have been around for a comparable time to the D2343P the contrast ratio ranges from Mega Contrast (worst) to 100000000:1 (best).
It may also be worth considering one of the alternative flatpanel monitors that have a 50000000:1 dynamic contrast ratio currently available including because of it's better review score, the Asus PB238 (£169.77).
PC screens with a higher contrast ratio that might also be worth considering include the VG248QE (£219.97) (80000000:1), the MX239H (£168.97) (80000000:1), or the PA248QJ (£400.84) (80000000:1) all from Asus which also has a higher rating.