Clarify that royalty holder revenue/NPV are pre-tax

Author: softwareengineerprogrammer

docs/SAM-Economic-Models.md

@@ -180,9 +180,10 @@ Output Parameters:
 1. `Average Annual Royalty Cost`: The developer's average annual royalty expense over the project's lifetime after
    construction is complete (Year 1). The same value is also output as `Royalty Holder Average Annual Revenue`. The
    individual royalties for each year are included in the cash flow line item `O&M production-based expense ($)`.
-1. `Royalty Holder Total Revenue`: The total undiscounted royalty income over the project's lifetime.
-1. `Royalty Holder NPV`: The Net Present Value of the royalty holder's income stream, calculated using the
-   `Royalty Holder Discount Rate`.
+1. `Royalty Holder Total Revenue`: The total gross (pre-tax), undiscounted royalty income over the project's lifetime.
+1. `Royalty Holder NPV`: The pre-tax Net Present Value of the royalty holder's income stream, calculated using the
+   `Royalty Holder Discount Rate`. This is a pre-tax value because the model does not account for the royalty holder's
+   specific tax liabilities.
 
 [Royalties example web interface link](https://gtp.scientificwebservices.com/geophires/?geophires-example-id=example_SAM-single-owner-PPA-4)
 

src/geophires_x/Economics.py

@@ -2182,7 +2182,10 @@ def __init__(self, model: Model):
             UnitType=Units.CURRENCY,
             PreferredUnits=CurrencyUnit.MDOLLARS,
             CurrentUnits=CurrencyUnit.MDOLLARS,
-            ToolTipText="Net Present Value (NPV) of the royalty holder's cash flow stream."
+            ToolTipText=f"The pre-tax Net Present Value (NPV) of the royalty holder's income stream, "
+                        f"calculated using the {self.royalty_holder_discount_rate.Name}. "
+                        f"This is a pre-tax value because the model does not account for the royalty holder's specific "
+                        f"tax liabilities."
         )
         self.royalty_holder_annual_revenue = self.OutputParameterDict[
             self.royalty_holder_annual_revenue.Name
@@ -2191,7 +2194,7 @@ def __init__(self, model: Model):
             UnitType=Units.CURRENCYFREQUENCY,
             PreferredUnits=CurrencyFrequencyUnit.MDOLLARSPERYEAR,
             CurrentUnits=CurrencyFrequencyUnit.MDOLLARSPERYEAR,
-            ToolTipText="The royalty holder's annual revenue stream from the royalty agreement."
+            ToolTipText="The royalty holder's gross (pre-tax) annual revenue stream from the royalty agreement."
         )
         self.royalty_holder_total_revenue = self.OutputParameterDict[
             self.royalty_holder_total_revenue.Name
@@ -2200,7 +2203,8 @@ def __init__(self, model: Model):
             UnitType=Units.CURRENCY,
             PreferredUnits=CurrencyUnit.MDOLLARS,
             CurrentUnits=CurrencyUnit.MDOLLARS,
-            ToolTipText='The total (undiscounted) revenue received by the royalty holder over the project lifetime.'
+            ToolTipText='The total gross (pre-tax), undiscounted revenue received by the royalty holder over the '
+                        'project lifetime.'
         )
 
         model.logger.info(f'Complete {__class__!s}: {sys._getframe().f_code.co_name}')

src/geophires_x_schema_generator/geophires-result.json

@@ -174,17 +174,17 @@
         "AddOns Payback Period": {},
         "Royalty Holder NPV": {
           "type": "number",
-          "description": "Net Present Value (NPV) of the royalty holder's cash flow stream.",
+          "description": "The pre-tax Net Present Value (NPV) of the royalty holder's income stream. This is a pre-tax value because the model does not account for the royalty holder's specific tax liabilities.",
           "units": "MUSD"
         },
         "Royalty Holder Average Annual Revenue": {
           "type": "number",
-          "description": "The royalty holder's annual revenue stream from the royalty agreement.",
+          "description": "The royalty holder's gross (pre-tax) annual revenue stream from the royalty agreement.",
           "units": "MUSD/yr"
         },
         "Royalty Holder Total Revenue": {
           "type": "number",
-          "description": "The total (undiscounted) revenue received by the royalty holder over the project lifetime.",
+          "description": "The total gross (pre-tax), undiscounted revenue received by the royalty holder over the project lifetime.",
           "units": "MUSD"
         }
       }