CSV because that's what our CRM database outputs. Its not actually a great system, mainly because no one who actually uses it regularly was involved in choosing it. We were going to get the upgraded version of our old system, but then one of the owners golf buddies recommended it, so it became the be-all-and-end-all (its actually a horrible system designed for a rental style business like car rentals rather than a stock sales based business with a load of mediocre stuff tacked onto the side of it, half of which is actually no use. I spend half my life making data analysis spreadsheets because it can't do it, but its all we've got to work with).

And again, because of the boss, it does have to be a clickable link. He's pretty OCD so the idea of having something like

https://www.ABCD.com/stuff/?f=123456...&salesman=Fred

in the email as text rather than a link saying "click here" would be unthinkable. He can't even tolerate us having a spare monitor, tower and cables in a cupboard in the back of the stores room so that we have a fall back if something breaks. The idea of something going to customers which wasn't all pristine and perfect would be criminal. And he's no more computer literate than his new marketing manager, in his eyes anything is doable, everything is straightforward and nothing will take longer than half an hour to do. If it does, its not down to the complexity of the system or an inherent limitation of the system, or even "Its processing 110,000 records of 50 columns to produce 70 different stats so its gonna take a little while to process". If its not done the way he wants in the time scale he wants, you're clearly not doing it right.