(a) The base year roll for each municipality is the 1989 roll except that for certain municipalities, the base year rolls are as follows:

1. (1) For the city of New York, the 1990 assessment roll.
2. (2) For the Nassau County roll, the 1990 county assessment roll.
3. (3) For a homestead assessing unit which uses the dual tax rate provisions of section 1903 of the RPTL for the first time for the levy of taxes against the 1990 or 1991 assessment roll, the first roll upon which dual tax rates are used.
4. (4) For a newly incorporated municipality, the first available final assessment roll. If a survey subsequent to the 1992 survey has begun, the determinations of sample class size, number of intervals, interval sample size, boundary and content of intervals and supplemental sample shall be made in accordance with the procedures for such subsequent survey.
5. (5) For a municipality in which there has been a change in level of assessment of 15 percent or more on the 1990 assessment roll, the 1990 assessment roll.
6. (6) For a municipality in which 50 percent or more of the parcels in roll section 1 and 6 have a change in assessment for equalization purposes, as reported on part 2 of the 1990 assessor's report, the 1990 assessment roll.
7. (7) For a city or town within a county in which 1990 assessment rolls would otherwise be collected for a majority of the cities or towns, the 1990 assessment roll.

8. (8) For a city or town which meets each of the following criteria, the 1991 assessment roll:

   1. (i) there has been a change in level of assessment of 15 percent or more on the 1991 assessment roll, and/or 50 percent or more of the parcels in roll sections 1 and 6 have had a change in assessment for equalization purposes, as reported on part 2 of the 1991 assessor's report; and
   2. (ii) the city or town provides all inventory records of assessment roll parcels and sales, and ORPTS has deemed the records to be of sufficient quality for use in the 1992 market value survey; and
   3. (iii) the inventory records are provided in a format readily usable by ORPTS.
9. (9) For all other villages, a base year roll is not designated.

(c) Where the survey base year roll of a prior survey is reused pursuant to this section, the following procedures shall be followed:

1. (1) The survey shall be performed on the classified roll prepared for the prior survey.
2. (2) The stratification for the survey shall be the same as was used for the prior survey.
3. (3) The sample parcels that were appraised for the prior survey shall be reappraised for the survey.
4. (4) The data collected for the prior survey appraisals may be reused when appraising the sample parcels for the survey.
5. (5) The supplemental sample determined for the prior survey shall be reused for the survey.