The foreword to this report says "the value of informal care has increased to exceed $40 billion per annum in 2010, 33% higher than in 2005". It says this is based on $31 per hour replacement costs. Probably, some of the value is estimated based on conjugate/centre-based care - so better care would be more expensive.

This report is not autism/ASD specific ... but is contains valuable and relevant material.

see http://carersaustralia.com.au/storage/Economic-Value-Informal-Care-Oct-…