I agree.assume_R said:Or, more specifically, the index (the decision) is dependent not only on the TC but also on the current depth. This is probably non-linear, in as the deeper you are, the more the depth becomes important.
I suspect that for the most part indices will be fairly stable but when you approach running out of cards they could flop around like a fish out of water.
I used to have a bunch of tables on my website that showed how insurance indices varied for Hi-Lo and KO as a function of hand composition, running count and number of cards remaining for 1,2,4,6,8 decks. Insurance indices are simpler because all that is needed is probability of a ten as dealer's hole card.
Below is data for insuring A-A and T-T for single deck and 8 decks using Hi-Lo.
Hand composition is much more of a factor for single deck.
Indices may be most stable when 50% of shoe is dealt.
Code:
Single deck Hi-Lo
[u]RC Num Cards TC[/u]
A-A <=-3 Never insure <=-3
-2 >=42 -2.48
-1 >=22 -2.36
0 Exactly 2, >=4 0
+1 Always insure
T-T <0 Never insure <0
0 Exactly 2 0
+1 <=17 +3.06
+2 <=34 +3.06
+3 <=42 +3.71
+4 Always insure
8 decks Hi-Lo
[u]RC Num Cards TC[/u]
A-A <0 Never insure <0
0 Exactly 2 0
+1 <=17 +3.06
+2 <=38 +2.74
+3 <=58 +2.69
+4 <=78 +2.67
+5 <=98 +2.65
+6 <=119 +2.62
+7 <=139 +2.62
+8 <=159 +2.62
+9 <=179 +2.61
+10 <=198 +2.63
+11 <=218 +2.62
+12 <=238 +2.62
+13 <=257 +2.63
+14 <=276 +2.64
+15 <=294 +2.65
+16 <=312 +2.67
+17 <=329 +2.69
+18 <=344 +2.72
+19 <=357 +2.77
+20 <=367 +2.83
+21 <=374 +2.92
+22 <=379 +3.02
+23 <=381 +3.14
+24 <=383 +3.26
+25 <=384, 384* +3.39
+26 Always insure
T-T <0 Never insure <0
0 Exactly 2 0
+1 <=14 +3.71
+2 <=30 +3.47
+3 <=46 +3.39
+4 <=62 +3.35
+5 <=78 +3.33
+6 <=94 +3.32
+7 <=110 +3.31
+8 <=126 +3.30
+9 <=142 +3.30
+10 <=158 +3.29
+11 <=174 +3.29
+12 <=189 +3.30
+13 <=205 +3.30
+14 <=220 +3.31
+15 <=236 +3.31
+16 <=251 +3.31
+17 <=266 +3.32
+18 <=281 +3.33
+19 <=295 +3.35
+20 <=309 +3.37
+21 <=322 +3.39
+22 <=334 +3.43
+23 <=345 +3.47
+24 <=354 +3.53
+25 <=362 +3.59
+26 <=367 +3.68
+27 <=371 +3.78
+28 <=374 +3.89
+29 <=376 +4.01
+30 <=377 +4.14
+31 <=378, 378* +4.26
+32 Always insure