Are you ready for Blue Monday, the day that falls this year at the start of this week, calculated by former Cardiff University psychologist Cliff Arnall in 2005 to be the most depressing 24 hours in the calendarArnall’s damning conclusion about the third Monday in the first month (which he has since tried to counter) was based on analysis of data, such as consumer surveys, divorce filings and weather reports. The main conclusion many of us draw from this analysis is that not all academic research is useful to society.If you are a world leader or senior executive at least you have the World Economic Forum in Davos to distract you from the January blues. The FT Live team will also be at the Swiss resort town, hosting several in-person and digital events in which leaders in policy, business and finance will share insights into the big issues being debated. You can view the events and register for free hereFor the rest of us, we will just have to live with the grim economic news going into 2023 and hope things can only get better.If you’re in the UK, the dominant reality is mass strike action. This might not yet be near to being a second “winter of discontent”, at least according to my colleague Jonathan Guthrie, but another strike ballot among ambulance workers is due this week while the University and College Union will announce a wave of 18 new strike days this week covering 150 British universities in February and March after its members voted last week to reject…