"[3] Variations of the story have been repeatedly reused by other companies in press releases, with 2014 seeing Blue Monday invoked by legal firms and retailers of bottled water and alcoholic drinks.
[4] Some versions of the story purport to analyse trends in social media posts to calculate the date.
[7] The formula uses many factors, including: weather conditions, debt level (the difference between debt accumulated and ability to pay), time since Christmas, time since New Year's resolutions have been broken, low motivational levels, and the feeling of a need to take action.
No units are defined; the lack of any explanation for what is meant by "weather" and "low motivational levels" means the dimensional homogeneity of the resulting formula cannot be assessed or verified, rendering it meaningless.
British science writer Ben Goldacre has observed that Arnall's equations "fail even to make mathematical sense on their own terms", pointing out that under the 2006 equation, packing for ten hours and preparing for 40 will always guarantee a good holiday, and that "you can have an infinitely good weekend by staying at home and cutting your travel time to zero".