### Data upload

Please prepare data in a single Excel file on separate tables for each measured value (KW, 
Kennwert) as shown in the below example. Table and File names are not evaluated. Instead, 
each table is expected to contain the metadata in rows 1-2 and the measurement data from 
row 4 on wards. Column names need to be exactly as in the example and should match the 
desired format (e.g. `Value` and `Date` columns should be of numeric and date format 
respectively).

![**Info** Excel format for LTS data. Cell background indicates cell format as text (blue), numeric (green) or date (red). The `Comment` column is optional.](fig/L_Modul_Import.png)

The `File` column can be used to reference the data source for traceability of measurement
values. The `Comment` column can be used to provide additional information.

The meta data information can not be further edited in *eCerto*. Hence, the user should carefully
consider the provided data. `U_Def` for example should specify which uncertainty value was
originally certified and is provided in `U`. This can be one out of five potential options:

- `1s` or `2s` indicating the simple or double variance
- `CI` confidence interval
- `1sx` or `2sx` indicating the relative simple or double variance

Other values will not be recognized correctly. Most meta data values will be used for plot
annotations and in the LTS report only and can be omitted. However, to comply with the rules
for good scientific practice it is recommended to provide them.