Australian DSL costs have fallen 15 per cent since 2004, and are set to drop a further 11 per cent by the end 2006.
The figures, which saw Australians averaging $66 on DSL in December 2004, project expenditure to fall as low as $50 by the end of 2006.
This is in line with global spending which has fallen 9.3 per cent since the beginning of this year.
Telsyte analyst Warren Chaisatien said the falling figures are relative to the adoption of broadband across the globe.
"These figures are a good representation of an overall fall in broadband costs," Chaisatien said.
"They reflect strongly on the adoption of [broadband] technology, as DSL represents about three quarters of the [Australian] broadband market share."
Overall, Australian broadband costs have fallen 21 per cent ($67) since December 2004 and 9 per cent ($58.20) from last year's figures.
Point Topic Research, which commissioned the global study, noted Japan had the best broadband offerings with fiber-to-the-node (up to 100Mpbs) costing $25.90 per month.
"Some operators offer 100Mbps for $25.90 per month, which is lower than the worldwide average for broadband over cable modem," a Point Topic spokesperson said.