Add signs and formatting to inputs

[greyhillman]

Problem

For currency amounts that a user enters, it can be hard to determine if they're entering ten thousand or a hundred thousand as there's no quick visual on how many zeroes there are.

Also, it's not easy to see which inputs are

• percents,
• years, or
• amounts

Current solution

The type of most fields are understood because of their labels ("Years" means years, "Rate of Return (%)" shows the sign) or the descriptions ("... rate ...", "How much" so amount).

Alternative solution

A user should be able to

• type "10000" into an amount input and have it displayed as "$10,000"
• type "3.44" into a percent input and have it displayed as "3.44%"
• type "35" into a year input and have it displayed as "35 years"

Benefits compared to current solution

• quicker to see the units of a field
• quicker to see how many zeroes you have

Costs compared to current solution

• complexity of typing in something but having it display differently in the same place.