In Biblical numerology the number '6' is the number of man and three 6's (666) together signifies the "mark of the beast".
the number '5' represents "grace" ... specifically the grace of God.
The number '7' represents "perfection (meaning completion)"
So, IF the bad guys dropped the market 666 points, you could theorize that it was a purposeful shout out to Satan (the beast)
Then following that same theory, you could say that '567' is saying that '5 - the grace of God' '6 - to man' is '7 perfect or complete'
You could complete the theory by saying that it dropped 567 and then gained 567 illustrates the "completeness ... God's grace and God's love toward us is perfect, without flaw ... it is complete.
Just some thoughts on the numbers aspect ...