A financial case to enable state health jurisdictions to invest in tobacco control.

State health departments bear considerable expenditure due to tobacco-related hospitalisations. We present a straightforward formula, based on aetiological fractions (attributable risks), with which to estimate tobacco-related expenditure in a way relevant and meaningful to state health departments and hospital managers. Tobacco was responsible for 43 571 hospitalisations in New South Wales in 1999-2000 alone, incurring $178 527 370 in hospital costs (nearly $500 000 per day). If the equivalent of a specified percentage of expenditure as calculated for one year were "invested" in tobacco control in the next year, then commitments to a substantive suite of health promotion programs could be made. For example, using our formula, a contribution of 3% would secure an annual tobacco control budget of $5 355 821 in NSW. Once securely funded, evidence-based tobacco control would reap dividends by reducing hospital expenditure and enhancing population health.