The standard I reference for unskilled work is any erosion of 15% or greater in terms of pace, persistence, concentration, attention across a two-hour work segment is work preclusive . 10% or greater precludes semi-skilled work . I have heard colloquial reference to studies of union production line workers where productivity is about 80% and employment is sustained.
Unless you can find authoritative data to support a number, I think it's your best estimate based on experience. Remember - people aren't machines, wages of $7.50 and hour or so has it's limits as far as quality of worker and productivity.
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Mitchell Schmidt
Vocational Case Manager
m.a.schmidt@comcast.net
State College, PA United States
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