Keep in mind that a lot of traffic from the region goes through proxies, VPNs, TOR etc., so I wouldn't consider these graphs too accurate.
I wonder how many Iranian users actually use bitcoin WITH their own IP. I would suspect the average computer savvy paranoid bitcoin user would use a VPN or Tor in fear of administrative punishment.
In Iran, everybody uses VPN, not only the computer savvy paranoid bitcoin user. Without VPN, you can't see 95% (by traffic) of the internet. Facebook is popular but blocked without VPN.