slebans
Enlightened
For anyone interested in a detailed breakdown how LED Package efficiency is derived, LER values, color theory etc., I highly recommend you at least read section 3.1.1 (starts on page 27) of the updated Solid-State Lighting (SSL) R&D Multi-Year Program Plan (MYPP).
http://apps1.eere.energy.gov/buildings/publications/pdfs/ssl/ssl_mypp2014_web.pdf
http://apps1.eere.energy.gov/buildings/publications/pdfs/ssl/ssl_mypp2014_web.pdf