BBS Network Token Price difference on Here and on exchanges.

Hey BBS fam hope you guys are doing great, i actually notice a thing from long time and i want to ask it that why there is huge difference in exchange rate of BBS to Dollar here and there on exchanges,

I noticed that when BBS network token price rotating round about 0.0177 and the exchange raye on BBS is about 0.0182 and they are change but difference remains, is there any rule of on bbs network of this difference or they are by default?