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 The 'websheet' folder corresponds to the WebSheet dataset, in which the folder 'Files' includes a random selection of 50 tables (spreadsheets), and the 'annotations.txt' provides their labeled regions of three types, i.e. IndexName, Index, and ValueName.
 
+# Pre-training data samples
+For Spreadsheet, Wiki Table, and Wdc Table, respectively.
+
+For spreadsheet tables, the json file contains keys as follows:
+
+T: cell text (explicitly revealed to humans, e.g.,58.50%)
+
+V: cell value (internally stored in spreadsheets, e.g., 58.5)
+
+NS: number string (internally stored in spreadsheets,e.g., 0.00%)
+
+DT: data type (internally stored in spreadsheets, text=0,number=1,data_time=2,percentage=3,currency=4,others=5)
+
+HF: if has formula, 0 or 1 (if a cell contains a formula in a spreadsheet)
+
+A1: formula string with A1 form (absolute cell reference)
+
+R1: formula string with R1C1 form (relative cell reference)
+
+LB: if has left border, 0 or 1
+
+TB: if has top border, 0 or 1
+
+BB: if has bottom border, 0 or 1
+
+RB: if has right border, 0 or 1
+
+BC: if has non-white background color, 0 or 1
+
+FC: if has non-black font color, 0 or 1
+
+FB: if has font bold, 0 or 1
+
+I: if has font italic, 0 or 1
+
+HA: horizontal alignment (center=0, center_across_selection=1,distributed=2,fill=3,general=4,justify=5,left=6,right=7)
+
+VA: vertical alignment (top=0,center=1,bottom=2,justify=3,distributed=4)
+
+O: operator of the formula, only used in ForTap
+
+FormulaNode: parse tree of the formula, only used in ForTap
+
+FormulaType: indicating if the formula reference one or more cells in other spreadsheets or files. Only used in ForTap