Some users were using last value, as the first value and vice versa. This ambiguity has been addressed and the descriptions clearly state what each calculation will return.

Remember, when you use historical calculations, they do NOT calculate on the first record ever entered (as there is not history). But, additional records will show the correct value.

The firstvalue calculation shown here calculates the first ever entered value.

In this example, the lastvalue will return the data point entered last on the system (e.g. most recent date).

You can write in historical calculations to include the value entered on that day. The example here shows that the first value ever on all existing data will be returned, or the data point from today will be used (slightly redundant for use with the firstvalue calculation as the first value will only ever be returned).

You can write in historical calculations to include the value entered on that day. The example here shows that the last value from all of the existing data will be returned, or the data point from today will be used (e.g. today's data). Again not a good example of the use of this field.

YOu can see here that the first ever entered value (first value) will be calculated from the 13th January data; this will return 1.0.

The last ever entered value will change to show the value before the current one (if using lastvalue (Historical Number), or to return the last ever entered value (if using lastvalue(Historical Number, Number). The image in the step below shows the output for each calculation

The image here shows that the firsvalues calculations always returns the first value ever entered. The Last Value shows the last entered value historically (e.g from the previous record), or the last ever entered value (across all records).