a downstacker for paperboard sheets includes a sheet speed reducing shingler positioned in the stacking station and forming a shingling nip with the top sheet of the continuously descending stack . the shingling nip is positioned to engage and nip the next following sheet simultaneously with engagement of the stacking station backstop by the preceding sheet , thereby obviating sheet marking by an overrunning nip roll . a false backstop is periodically interposed to define a stack separation level and create an offset in the stack which engages the end of a separating fork as the continuously forming stack descends to facilitate insertion of the fork supporting into the stack . the fork provides interim support for the upper stack portion which continues to form while the lower stack portion is rapidly discharged .