I booked a ticket from San Francisco to Tel Aviv leaving in August and returning in January with the possibility of changing the ticket for an extended time. The airfare I booked was $1730 while other airlines were charging $1,800+.

All the websites were turning prices of around $1800+ and with the state of the gas prices etc. I thought that by booking now would lock in a good rate.

I am flying on a Brussels Airlines Codeshare operated by Lufhtansa from SFO-TLV via BRU and FRA and from TLV-SFO . Every flight except the BRU-TLV is on Lufthansa. On Lufthansa's website it would have cost me more.

I wonder why is it less expensive to book on a codeshare?

It seems as if the airfares won't go down for my dates as I am going to be gone for an extended time. Normally the airfare is $1,100 for a 30 day return.