How to calculate the change in the exchange rate between the current value and the previous one in rubles and percentages?

Question

Google Sheets

Hello. I’ll make a reservation right away, I’m a kettle in the tables, otherwise I wouldn’t ask for help.
There is a Google spreadsheet with a script in it, which parses the dollar to ruble exchange rate from the Central Bank website and records the data received. See the first tab Parser, the rest are not important.
It is necessary that in column C the changes in rubles are displayed, rounded to hundredths. For example, 0, 22, that is, 22 kopecks.
And in column D the same change was displayed, but already in percent. 0.011% (conditional).
For example, on the date 02/01/2018 the rate was 56.18 and on 02/02/2018 it became 56.26. So, in column C for 02.02.2018, you need to display the change -0.08 A in column D, display -0.045% (rounded to 3 decimal places)
It seems to me that in order for everything to work correctly, the formula must be built on the basis of subtracting even and odd series, since courses are not published every day, there are days off.
Another nuance is that the table is automatically expanded, that is, the rates for new dates are automatically written to the end of the table and it is necessary that the calculations continue to work. Well, I'll clarify this just in case.
Help, please, to solve the problem.