Excel：根据日期和时间计算平均每日天然气使用量

Question

awkward question to word. I'm using Excel and would like to calculate the average usage of gas in my house. I have got a list of times and dates which I write down when I get chance or remember, is there a good way to do this?

I would like to use cell formulas by the way.

An example of the data I have to work with:

  Date/Time         Gas   Electric
25/01/15 01:48    £10.62    £3.38
                           +£5.00
26/01/15 01:48    £8.56     £6.92
26/01/15 02:00    £8.18     £6.45
27/01/15 13.19    £7.44     £6.03
27/01/15 18.00    £7.06     £5.57
27/01/15 19:50    £7.06     £5.41
27/01/15 21:14    £6.97     £5.26

Edit: Using TriHard8's answer, this is what is produced

Does this mean that 0.70 pence is used each hour based on the two times?

Edit 2: Still getting negative numbers :S

Answer 1

Gas used between 2 dates/times divided by ((Date2 + Time2) - (Date1 + Time1)). (10.62 - 8.56) / ( (26/01/15 + 01:48) - (25/01/15 + 01:48) )

Put this formula into H6: =( F5 - F6 ) / ( (D6+E6) - (D5+E5) ) This will be use per day. It doesn't matter if you compare 2 measurements from the same day, or over 20 days, it will be the average per day.

You need to make sure that you format the resulting cell to be a number, with whatever precision you'd like.