14 .49 .66 .67 .74 .72 .67 1.00 .57 14C .92 .93 .96 .98 .93 .98 .97 .97 15 .56 .68 .70 .95 .94 15C .79 .80 .59 .66 .67 .70 .62 .54 16 .49 .53 .74 .79 .81 .77 .69 16C .34 .28 .50 .54 .24 .24 .69 .51 17 .53 .50 .53 .05 .78 17C .17 .15 .24 .11 .40 .34 18 .57 .38 .33 .45 .51 18C .17 .20 .30 .34 .10 .06 .09 .03 19 .95 .99 .94 .98 .94 .88 .93 19 .38 .45 .30 .37 .67 .40 .09 .31 20 .13 .37 .33 .16 .23 20C .63 .75 .56 .88 .67 .44 .78 .86 21 .83 .89 .84 .76 .76 .80 .44 21C .67 .77 .55 .61 .81 .67 .62 .57 22 .85 .81 .91 .78 .95 .92 .99 22C .83 .92 .93 .97 .82 .91 .33 .89 23 .36 .45 .36 .70 .78 .63 23C .73 .74 .70 .82 .55 .53 .36 .62 24 .59 .69 .67 .81 .85 .89 .66 24C .62 .63 .59 .71 .67 .67 .86 .86 25 .47 .60 .57 .63 .53 .62 .78 25C .73 .74 .60 .64 .44 .91 .70 .79 26 .74 .89 .74 .85 .53 .54 .57 26C .76 .81 .70 .79 .84 .76 .40 .40 27 .11 .23 .16 .04 .18 .06 27C .07 .12 .12 .23 .10 .16 .30 .25 28 .86 .90 .87 .90 .97 .88 .78 .91 28C .87 .93 .83 .86 .88 .98 .94 TABLE XI (Continued) Showing percentile ratings of the two groups at the beginning and end of the six months' interval N[16] I.Q. Healy Total Possible Average Gain 1 .25 .27 .10 .29 .30 415 .05 1C .21 .15 .01 .12 .53 462 .089 2 .84 .89 .60 .66 .38 416 .063 2C .45 .51 .29 .18 -.07 358 -.011 3 .49 .44 .49 .51 .40 328 .066 3C .25 .32 .44 .45 .30 287 .05 4 .59 .59 .38 .22 168 .073 4C .27 .32 .71 .42 195 .14 5 .53 .71 .10 .42 213 .14 5C .89 .90 .77 .24 133 .08 6 .53 .77 .02 .55 229 .183 6C .37 .38 .04 .27 210 .09 7 .45 .71 .22 .07 .37 478 .062 7C .53 .71 .34 .59 .74 393 .148 8 .45 .34 .70 -.50 303 -.125 8C .67 .81 .33 .52 .10 241 .025 9 .27 .46 .23 .39 .71 375 .118 9C .35 .40 .73 .89 .72 217 .12