There are a number of economic effects of Daylight saving Time (DST). Historically, Daylight Saving Time has been supported by business interest groups, as more daylight during the summer months generally means extra shopping hours. With brighter afternoons and evening, consumers are more liking to continue shopping until later in the day, meaning increased profits for retailers. One of the staunchest supporters of DST is the American convenience store chain 7-Eleven, which quotes significantly higher takings as a reason to keep Daylight Saving.
Some of the health benefits attached to Daylight Saving Time can also lead to higher rates of productivity, as increased levels of sunlight can help people who suffer from Seasonal Affective Disorder (SAD) or depression. It can also lead to increased involvement with outdoor sport, with the golf industry in particular benefiting (in fact, the first major proponent of Daylight Saving Time, William Willett, was an avid golfer and believed that the scheme would do the sport untold good. Woodrow Wilson, also a golfer, actually twice vetoed a repealing of Daylight Saving Time, some say on the grounds that it would affect his favourite pastime). It has also been argued, with substantiation, that Daylight Saving Time has the potential to act as a powerful energy saving initiative, as more hours of sunlight during the day mean less energy spent on lighting and heating, both domestically and on a national scale.
Daylight Saving Time does, however, result in a number of economic and social changes that, some have argued, actually decrease productivity and increase business expenditure. Alterations to sleeping patterns can mean employees have to make substantial changes to their routines, and some studies have shown that absenteeism goes up in the first few weeks of the introduction of Daylight Saving. It also has a negative effect on businesses and industries whose working and opening hours are determined by the sun. Agriculture is perhaps the best example of a sector that genuinely struggles to adapt to the changes brought about by the clocks changing. Livestock have trouble getting used to alterations in routines like milking, and yields have been shown to drop slightly during the summer months when DST is in operation.
Businesses that rely on an evening atmosphere have also been shown to suffer, with drops in theatre bookings a good example. Television networks have cited Daylight Saving Time as a reason for drops in prime-time viewer ratings, as more people who would stay in and watch television if it were dark are outside spending time in the sun. DST can also have a negative effect on technology and infrastructure, as every year broad changes have to be made to computer and phone networks in order to keep them up to date with time shifts. Even the relative energy gains that come about as a result of Daylight Saving have been contested, with many suggesting that higher levels of sunlight during the day leads to increased activity, which in turn means more energy is being used for things like transport and outdoor events.