Prior to examining todays verse we make some light descriptive comments on the non-verse method.
• When Rashi gathers a collection of verses and infers from numerical computations we say Rashi uses the Spreadsheet method.
• When Rashi clarifies a verse with a geometric diagram we say he is using the geometric or diagrammatic method.
• The spreadsheet and diagram method are examples of the category of non-verse methods - that is clarifications of the verse by knowledge domains outside the verses - outside domains like spreadsheets and geometry.
• So if Rashi clarifies the verse with archaeological finds we are also using the non-verse method.
• Finally We also say the non-verse method is used when Rashi fills-in background with plausible real-world events. Since these fill-ins are not derived from the Biblical text but rather are derived from the real-world we consider them analogous to the use of diagrams and computational spreadsheets.
The common denominator of
• Numerical spreadsheets
• Geometric diagrams
• plausible real world fill-ins and backgrounds
• archaeological finds
is inference from non-verse material. Todays example particularly illustrates this.

Verse Gn31-15 discussing Jacob's plan to desert his father-in-law states Are we not counted by him as strangers? for he has sold us, and has quite devoured also our money Rashi explains the underlined phrase for he has sold us, by filling in with real-world background: In most marriages the father of the bride provides a monetary dowry to help get the couple started. But in Jacob's marriage the exact opposite happened: Jacob had to pay his father-in-law, by working for him for 7 years. Hence the Biblical phrase he sold us.

To recap, Rashi comments on the verse by
• bringing in the custom of the father of the bride giving a dowry to his future son-in-law
• contrasting the gift of the father-in-law to the son-in-law with the purchase requirement of 7 years of labor to obtain Rachel.
Because this comment uses real-world vs non-textual material we say the spreadsheet method is being used.

Advanced Rashi:This Rashi is also an example of application of archaeological methods. Numerous fragments uncovered from ancient times shows a certain balance in dealing with monetary manners:
• Inheritance went to the males while dowrys went to the females.
Note that this is a strong example of equal but different. Indeed if the woman would both inherit and receive a dowry her inherited money would most likely be given to her husband which would means that the women are getting double. (If women had no dowry they would be less attractive as marriage partners). This duality - inheritance /dowry - is further complicated by two more facts.
• The dowry was given during the lifetime of the parents (and hence more certain) while the inheritance was only given at death.
• Finally the inheritance was a legal claim (it could be recovered in court if denied) while the dowry was a strong custom which however was not subject to court review.
So Laban, crook par excellence, shows his real metal by denying his daughters the dowry they deserved - it was against all social custom but was not recoverable in court. This archaeological background enhances the appreciation of the comments of the daughters We are non-family...we are getting nothing monetary from our father We have no economic incentive to stay. As already indicated algebraic, geometric and archaelogical driven Rashis are classified as non-verse.