A store was vandalized repeatedly over a six-month period . When discussing the problem with a friend, the store owner mentioned having heard that bright lighting around the perimeter of commercial establishments had been known to reduce the incidence of vandalism. Three months later, the store owner reported to the same friend that there had been no incidents of vandalism since their previous conversation. The friend concluded that bright lighting had been installed around the perimeter of the store. Each of the following, if true, would call into question the friend's conclusion EXCEPT: ['There had been an increase in police patrolling of the area.', 'The store owner reported that all the stores adjacent to the perimeter also experienced a reduction in vandalism, although stores one block away did not.', 'The store owner brought in a watchdog to protect the store from vandals.', 'Bright lights must be specially ordered from a security company, and installation by the company usually takes at least five months.']