One more key point that I want to make along these lines -
When you know that a few hours of effort by a programmer at the source can save many hours
(over time) of effort for every one
of your customers (OK, backtesters only in this case, and god-bless the non-backtesters for their participation in the markets
) - and you refuse to make that effort, you are displaying disregard for your customers and potential customers by placing zero value on their time.
It's a mis-conceived business decision, IMO, to save a small amount of developer's effort at the cost of foisting an even higher burden (over time) across your entire customer base.
The whole point of computers and software is to streamline and empower human life. If you get this, word gets around. If you don't, likewise. That's the opportunity and the peril of the digital age.
What I write, I write to remind (not to offend), because observation of current facts suggests that reminding might be helpful (for all).