It was determined the cost economically was far higher than the returns.

Not quite.

In the end the project ran for four years, concluding in 1979, but the data collection lasted for only two years and virtually no analysis was done by project staff. New governments at both federal and provincial levels reflected the changing intellectual and economic climate. Neither the Progressive Conservative government of Joe Clark in Ottawa nor Sterling Lyon’s Tories in Manitoba were interested in continuing the GAI experiments. The fate of the original data—boxes and boxes of paper files on families containing questionnaires related to all aspects of social and economic functioning—was unclear. They were stored in an unpublicized location by the Department of National Health and Welfare. In the end, only the Winnipeg sample, and only the labour market aspects of that sample, was ever made available. The Dauphin data, collected at great expense and some controversy from participants in the first large scale social experiment ever conducted in Canada, were never examined.

This study involved using one small town, Dauphin, as a a test for what happens when everyone in the population qualifies for the basic income. The study ran out of money long before the researchers originally thought it would, and the majority of the data wasn't analyzed until relatively recently.

The general result found in all the experiments was that secondary earners tended to take some part of the increased family income in the form of more time for household production, particularly staying home with newborns. Effectively, married women used the GAI to finance longer maternity leaves. Tertiary earners, largely adolescent males, reduced their hours of work dramatically, but the largest decreases occurred because they began to enter the workforce later. This delay in taking a first job at an older age suggests that some of these adolescent males might be spending more years in school. The biggest effects, that is, could be seen as either an economic cost in the form of work disincentives or an economic benefit in the form of human capital accumulation.

New mothers and teenagers weren't required to spend as much time working

Money flowed to Dauphin families from MINCOME between 1974 and 1978. During the experiment, Dauphin students in grade 11 seemed more likely to continue to grade 12 than their rural or urban counterparts, while both before and after the experiment they were less likely than their urban counterparts and not significantly more or less likely than their rural counterparts to complete highschool. Grade 11 enrolments as a percentage of the previous year grade 10 enrolments show a similar pattern.

Highschool graduation rates went up

Overall, the measured impact was larger than one might have expected when only about a third of families qualified for support at any one time and many of the supplements would have been small. …At the very least, the suggestive finding that hospitalization rates among Dauphin subjects fell by 8.5 percent relative to the comparison group is worth examining more closely in an era characterized by concern about the increasing burden of health care costs. In 1978, Canada spent $7.5 billion on hospital costs; in 2010 it was estimated to have spent $55 billion—8.5 percent of which adds up to more than $4.6 billion. While we recognize that one must be careful in generalizing potential health system savings, particularly because we use hospitals differently today than we did in 1978, the potential saving in hospital costs associated with a GAI seems worthy of consideration.

And hospitalization rates went down. There were other effects, like small businesses opening during the period of MINCOME and shutting down after, a possible decline in women under 25 having children, but none of this was evaluated for whether it was worth the money or not.