Here, I'd like to investigate just which division in baseball has been the most shakiest/most solid over the past years, back to 2008 specifically. I'll create a points system for this: We start with the final standings for 2008, and then for 2009, we give each team in that division one point for each spot moved up or down--better or worse does not count in this situation--and do the same from 2009-2010, from 2010-2011, and from 2011 to August 18, 2012. For example, if the Cardinals finished 2nd in the Central in 2011, but finished 1st in 2012, then they get 1 point for moving 1 spot up in the standings from the previous year. You'll likely ask, "the NL Central will certainly be more shaky, because they clearly have an additional team than the other 5, and the AL West is the opposite because they have one less than the other 5". For that, I've decided that for every team in the division, that's 2 points subtracted from the total. In the end, the division with the most points is the shakiest, while the division with the least points is the most solid (not the best, but the division with the least movement of its teams).

2008

AL East: TB, BOS, NYY, TOR, BAL.

AL Central: CHW, MIN, CLE, KC, DET

AL West: LAA, TEX, OAK, SEA

NL East: PHI, NYM, FLA/MIA, ATL, WAS

NL Central: CHC, MIL, HOU, STL, CIN, PIT

NL West: LAD, ARI, COL, SF, SD

For the first one, the points are in parentheses for the respective teams' movement in their division from 2008 to 2009.

2009

AL East: NYY (2), BOS (0), TB (2), TOR (0), BAL (0)

AL Central: MIN (1), DET (3), CHW (2), CLE (1), KC (1)

AL West: LAA (0), TEX (0), SEA (1), OAK (1)

NL East: PHI (0), FLA/MIA (1), ATL (1), NYM (2), WAS (0)

NL Central: STL (3), CHC (1), MIL (1), CIN (1), HOU (2), PIT (0)

NL West: LAD (0), COL (1), SF (1), SD (1), ARI (3)

So the points at the end of 2009:

AL East: 4

AL Central: 8

AL West: 2

NL East: 4

NL Central: 8

NL West: 6

Now, the standings for 2010. The points are for movement from their 2009 standing.

2010

AL East: TB (2), NYY (1), BOS (1), TOR (0), BAL (0)

AL Central: MIN (0), CHW (1), DET (1), CLE (0), KC (0)

AL West: TEX (1), OAK (2), LAA (2), SEA (1)

NL East: PHI (0), ATL (1), FLA/MIA (1), NYM (0), WAS (0)

NL Central: CIN (3), STL (1), MIL (0), HOU (1), CHC (3), PIT (0)

NL West: SF (2), SD (2), COL (1), LAD (3), ARI (0)

So now the total points as of the end of 2010:

AL East: 8

AL Central: 10

AL West: 8

NL East: 6

NL Central: 16

NL West: 14

The final standings for 2011, and the points accumulated by each team for their movement in their division from 2010 to 2011.

AL East: NYY (1), TB (1), BOS (0), TOR (0), BAL (0)

AL Central: DET (2), CLE (2), CHW (1), KC (1), MIN (4)

AL West: TEX (0), LAA (1), OAK (1), SEA (0)

NL East: PHI (0), ATL (0), WAS (2), NYM (0), FLA/MIA (2)

NL Central: MIL (2), STL (0), CIN (2), PIT (2), CHC (0), HOU (2)

NL West: ARI (4), SF (1), LAD (1), COL (1), SD (3)

So the points as of the end of 2011:

AL East: 10

AL Central: 20

AL West: 10

NL East: 10

NL Central: 24

NL West: 24

The standings as of today, August 18, 2012, and the points in parentheses for each team's movement within their division:

AL East: NYY (0), TB (0), BAL (2), BOS (1), TOR (1)

AL Central: CHW (2), DET (1), CLE (1), KC (0), MIN (0)

AL West: TEX (0), OAK (1), LAA (1), SEA (0)

NL East: WAS (2), ATL (0), NYM (1), PHI (3), FLA/MIA (0)

NL Central: CIN (2), PIT (2), STL (1), MIL (3), CHC (0), HOU (0)

NL West: SF (1), LAD (1), ARI (2), SD (1), COL (1)

So, the final points for each division:

AL East: 14

AL Central: 24

AL West: 12

NL East: 16

NL Central: 32

NL West: 30

Now, I'll deduct 2 points for each team in each division. With that, here are the final standings:

AL East: 4

AL Central: 14

AL West: 4

NL East: 6

NL Central: 20

NL West: 20

So, the NL Central and NL West are the most shaky, while the most solid are the AL East and AL West.