Avg 6 months = 1,87 posts per day. There is a slight recent increase these past 2 months, but nothing that shines of its own light.
Thus, it has been determined that a local board isn't required for the Bangladesh language. Although, it would be nice to get statistics from those that do have their dedicated section to be able to effectively compare the difference.
A bit off topic: If one inactive place turns into more active or very active, it sheds the light on something interesting or suspected behind the scene. What happened with the forum in last 3 months of 2017 is a good example. Come fast, go fast or just come to abuse the system (at least they feel they can).
Not completely off topic, because before implementing a new section for local languages it is probably a good idea to look at the long term outlook of the section, and whether there is a reason for spikes in activity from a particular demographic, and try to establish whether this is likely to continue. For an extreme example, if a country declared Bitcoin as their official currency we would likely see a dramatic increase in users from that country, and this would likely be a long term trend. However, if its due to a signature campaign specifically for a certain language then this isn't likely to continue if that signature campaign were removed.
Bangladesh users communicating in their local section haven't had any such rises, and the long term outlook is probably very much the same as previous years.