I am having a hard time understanding my energy contract, and looking for some help/clarification

I am still learning this so please bear with me.

I recently switched energy companies.

They quoted my monthly bill at $90

my contract states 500kWh 19.5cents 1000kWh 9.0 2000kWh 13.8

what does this mean? its 19 cents a kw but 9 cents a kW at 1000?

Sorry, i did not know where else to post this, any help is greatly appreciated