reculating the new cost basis

Hi

I have just realised that the consolidation of 3 for 1 has already been reflected in my etrade account.

I originally had approx 19,340 shares, but now I have 6447.

I am a newbie here and in the world of stock trading and I realised that my original cost basis has not changed. I originally purchased this at an avg price of $0.245. I thought that once the consolidation was reflected, the cost basis would also relfect the new change?

See below:
MON 6,447 0.245

Thanks
Rob