1. A computer system for using an undo stack to explore past actions and apply new actions to previous states in a data view, the computer system comprising: one or more computer processors; one or more computer readable storage media; program instructions stored on the computer readable storage media for execution by at least one of the one or more processors, the program instructions comprising: program instructions to provide a user interface allowing a user to perform operations on undo stack entries in a business analytics data view, wherein the performable operations include filtering data values, expanding data values, collapsing data values, drilling down on data values, drilling up on data values, applying formats to data values, showing totals as trailing, and showing totals as leading; program instructions to detect a first change in the business analytics data view; program instructions to, responsive to detecting the first change in the business analytics data view, display a first undo stack entry representing a state of the business analytics data view corresponding to the business analytics data view prior to the detected change, and a second undo stack entry representing a first current state of the business analytics data view; program instructions to, upon detecting the first change in the business analytics data view and displaying the first undo stack entry and the second undo stack entry, detect a second change in the business analytics data view; program instructions to, responsive to detecting the second change in the business analytics data view, display a third undo stack entry representing a second current state of the business analytics data view; program instructions to, upon detecting the second change in the business analytics data view and displaying the third undo stack entry, detect a third change in the business analytics data view; program instructions to, responsive to detecting the third change in the business analytics data view, display a fourth undo stack entry representing a third current state of the business analytics data view; program instructions to detect a selection of a branch operation for one of the first undo stack entry, the second undo stack entry, and the third undo stack entry; program instructions to, responsive to detecting the selection of the branch operation, apply the branch operation to the state of the business analytics data view represented by the branch operation's respective undo stack entry, wherein applying the branch operation creates and displays a new window that includes the undo stack and the business analytics data view represented by the branch operation's respective undo stack entry; program instructions to detect a selection of a copy operation for one of the first undo stack entry, the second undo stack entry, and the third undo stack entry; program instructions to, responsive to detecting the selection of the copy operation, apply the copy operation to the state of the business analytics data view represented by the copy operation's respective undo stack entry, wherein applying the copy operation makes the business analytics data view represented by the copy operation's respective undo stack entry available for reuse while remaining in the new current state of the business analytics data view; program instructions to detect a selection of a save as operation for one of the first undo stack entry, the second undo stack entry, and the third undo stack entry; program instructions to, responsive to detecting the selection of the save as operation, apply the save as operation to the state of the business analytics data view represented by the save as operation's respective undo stack entry, wherein applying the save as operation allows the user to save the business analytics data view represented by the save as operation's respective undo stack entry while remaining in the new current state of the business analytics data view; program instructions to detect a selection of one of the first undo stack entry, the second undo stack entry, and the third undo stack entry; and program instructions to, responsive to detecting the selection of one of the first undo stack entry, the second undo stack entry, and the third undo stack entry, return the business analytics data view to the state represented by the selected undo stack entry.