Nevertheless, authorities cite some evidence which could indicate that recent enforcement efforts have been effective. For instance, social insurance revenues have increased more strongly than employment since the start of the recovery, although the extent to which this is driven by enforcement efforts is difficult to disentangle from the effects of other policy changes, such as increasing minimum wages. Public opinion may largely see informal employment as an involuntary outcome for employees, and workers’ weak bargaining position suggests that informal work is indeed often not a choice of workers, notably during periods of slack labour markets. Imposing fines on workers indiscriminately is therefore not only politically difficult, but probably counter-productive as it can discourage employees from reporting employers’ infringements of applicable labour and tax laws.