Strong signals are actually a BAD indicator for intelligent life. Have humans ever detonated an entire star just to send a strong, but short and meaningless pulse signal? NO! Have we sent weak, but long and encoded signals? Yes, we do every day in fact. Truth is most signals the Earth itself is sending are so weak we would not be able to pick them up from only 4 light years away with our BEST equipment. This should easily explain to you why SETI has so far failed. I could remember wrong, but I believe years ago I read a strong candidate for the WOW signal was a reflection of Earth radio signals/radar beams back to SETI. Also the numbers you see circled are signal strength, not data. The researcher wrote "wow" simply because the signal was strong. Hence why he also circled a lone 7.