(xi)[ any expenditure incurred by the assessee, on or after the 1st day of April, 1999 but before the 1st day of April, 2000, wholly and exclusively in respect of a non-Y2K compliant computer system, owned by the assessee and used for the purposes of his business or profession, so as to make such computer system Y2K compliant computer system: [ Inserted by Act 27 of 1999, Section 22 (w.e.f. 1.4.2000).]