I see members requesting timeline updates in timeline threads.
Anyone with knowhow of Excel can go to this link
and download the Excel I made, then edit with relevant data. It has formulas for top-level calculations and also for Total Days and Total working days fields on each row. You need to put data as in example though and dates as dd/mm/yyyy. Also put "Yes" in Approved? column for auto count and calculation of averages. Then on Excel menu click copy to "Copy as image" and then upload attachment there in the relevant thread. Mine is October 2014
The Excel is in .xlsx format, but if you use Google Docs then you can change/edit there too as far as I know, haven't tried that part.
Threads might have "attachment threshold" so its probably better to go to User Control Panel
and delete the previous attachments and then upload new one. Or you can post a link from imgur or some other image sharing site if you fancy, I prefer the former method.
Hope this helps others.