Z}A:"pppA7@(Geographic region of the U.S.A7@VG.Difference in 1977 Per Pupil Expenditures ($)A7@S1-10QZ1O1A7@S)!-.750QZ)!O)!A7@S=-.50QZ=O=A7@SQ-.250QZQOQA7@Sd00QZdOdA7@S{a.250QZxOx0M;ddA7@bN.East0A7@N.Cent0iiA7@Mt.Pac0A7@0S.East0/R/RA7@DS.Cent0CBCBp0O{aO0Op!iT!P!"`!/RBh!2Ra!5V!CB6[!FFT!IJ!M;X0i>uik{0: g0"J"v|0/R)/R[029x2kJ05=5o0CBCBN0F/,F]|0I3Ia0M;>M;rpA&@qG A (A group of intervals pairs its level with each level above it)