you say that 64% of the guard relays and 51% of the exit relaysare are unpatched ?
These numbers are not based on relaycount but on guard/exit probability (so it takes a relay's contributed bandwidth/consensus weight into account).
If you are more interested in relay counts: 3754 out of 7268 relays are probably vulnerable (51%).
+------------+------------------+-----------------+ | cwfraction | guardprobability | exitprobability | +------------+------------------+-----------------+ | 0.586 | 0.639 | 0.518 | +------------+------------------+-----------------+
2016-02-23: +------------+------------------+-----------------+ | cwfraction | guardprobability | exitprobability | +------------+------------------+-----------------+ | 0.560 | 0.621 | 0.466 | +------------+------------------+-----------------+