2006 New York Code - Course Of Performance Or Practical Construction.

 
  Section 2-A-207. Course of Performance or Practical Construction.
    (1) If a lease contract involves repeated occasions for performance by
  either  party  with  knowledge  of  the  nature  of  the performance and
  opportunity for objection to it by the other, any course of  performance
  accepted or acquiesced in without objection is relevant to determine the
  meaning of the lease agreement.
    (2)  The  express  terms  of  a  lease  agreement  and  any  course of
  performance, as well as any course of dealing and usage of  trade,  must
  be  construed  whenever reasonable as consistent with each other; but if
  that construction is  unreasonable,  express  terms  control  course  of
  performance,  course  of performance controls both course of dealing and
  usage of trade, and course of dealing controls usage of trade.
    (3) Subject to the provisions of Section 2-A-208 on  modification  and
  waiver,   course  of  performance  is  relevant  to  show  a  waiver  or
  modification of any term inconsistent with the course of performance.