accessing
tweetsDivisionsByWeeks

	| weeks floor divisions |
	weeks := ((self newestTweet created - self oldestTweet created) days / 7).
	floor := weeks floor.
	(weeks - floor) > 0.4 
		ifTrue: [ floor = 0
			ifTrue: [ divisions := 1 ] 
			ifFalse: [ divisions := floor]] 
		ifFalse: [ divisions := floor + 1 ].
	^ divisions