I am creating an org chart of my team and I wonder if I can add the days, months OR Year an employee have since joined the company and if this can be automatically calculated each time the file is opened.
Unfortunately while MindManager has the ability to handle date arithmetic it doesn't make it very accessible to end users, except in relation to task management.
This does provide a workaround however, provided you are using either MM2018 or 2019 and the MAP add-in from Olympic Limited. The trick is to treat each employee's topic as a task. To do this you need two bits of information - a start date, obviously when the employee joined the company, and, unfortunately, an end date. What the actual end date is doesn't matter, but you have to have one, so the obvious thing to do is to give everyone the same end date well off in the future.
You then go to MAP's Extended Properties feature and in the Task Information section click on Start Date to add the start date as a topic property. You then go to the Timings and Status section and under Task Timing click on Task Days Elapsed to add this as a topic property. This should then display the number of days since the employee started work.
If you like you can add a calculated field as a tropic property in which you divide the Task Days Elapsed by 30 to give a reasonable but not strictly accurate count of the number of months. Both of these fields will automatically update whenever you open the map. Unfortunately there doesn't seem to be a way of limiting the number of places after the decimal point in calculated fields.
You can hide the task info display so that each topic shows only the topic properties - and looks less like a task. You can also hide individual topic properties so that you show only, say, the start date and the number of months. Also bear in mind that if you need to change the start date you will have to do that to the task info entry rather than editing the topic property directly.