By its nature, putting a price on the cost of sectarian division in Northern Ireland is always going to be an imprecise science. But whether it is £1.5bn a year, as estimated in a new report, or £1bn a year as the Alliance Party claimed in 2004, it is undoubtedly a tremendous drain on the public purse.
The latest report has been compiled by consultants Deloitte for the Stormont Executive, and Ministers will be considering its conclusions this autumn. The authors of the report have based their estimate on an examination of the costs of separate education systems and segregated housing areas.
In many instances, they say, the divide leads to "duplication or even multiplication" of service delivery because Protestants and Catholics are unwilling to live side-by-side or to share facilities.
These findings make uncomfortable reading but they will not come as a surprise to anyone living in Northern Ireland. The most obvious signs of a divided society are the flags and the murals, but this is a gulf that extends - albeit in a more discreet way - to middle-class areas.
Four decades of conflict have produced a society which is deeply fractured. But now that the terrorist campaigns are over, and a partnership administration is in place, hope must be high that the healing process will spread through society.
A new era of peace and reconciliation will not, however, come about of its own volition. Everyone has a role to play and cross-community groups such as One Small Step can give a lead by breaking down stereotypes and creating new linkages.
The day when a Catholic family feels happy to live on the Shankill Road, or a Protestant family on the Falls, is still distant. But incremental progress can be made and the more immediate goal must be to achieve a situation in which people are happy to live and let live, and no longer feel the need for protection from the peace lines.
It all boils down to a question of creating trust and if Ian Paisley and Martin McGuinness can work together, surely there is an onus on us all to re-examine our own attitudes. As the Executive is showing, Northern Ireland has everything to gain and nothing to lose if people can agree to co-operate and collaborate.
While the report shows it is possible to attempt to put a price on the economic cost of sectarianism, the extent of the emotional damage can still only be guessed at. In many interface areas, people are still living in fear, leading to above average levels of depression and dependence on medication.
The underlying message is that an absence of violence does not automatically mean that a sustainable peace has been created. Northern Ireland is still in transition and a new era of harmony has yet to be established. This is work in progress but for the sake of the next generation, it is a challenge to which politicians and people alike must rise.