Index of PERB Opinion Numbers Use the chart below to cross-reference PERB opinions (from 1981 to present) with citations in the DC Register. To order a copy of the publication, please click here. PERB Opinion Numbers:   (as of 10-1-02) 1 - 25 101 - 125 201 - 225 26 - 50 126 - 150 226 - 250 51 - 75 151 - 175 251 - 275 76 - 100 176 - 200 276 - 300       301 - 325 401 - 425 501 - 525 326 - 350 426 - 450 526 - 550 351 - 375 451 - 475 551 - 575 376 - 400 476 - 500 576 - 600       601 - 625     626 - 650     651 - 675     676 - 700