Initial documentation of the Program: tag.

Includes introduction of the section about making use of these tags.

accounts/config/config-accounts.ledger

@@ -41,7 +41,7 @@ account Accrued:Accounts Receivable:Main Org
 ;       to the assert in ever Expense account because of the following bug:
 ;               http://bugs.ledger-cli.org/show_bug.cgi?id=953
 
-define expenseChecker() = (tag("Receipt") !~ /^\s*$/ or tag("Invoice") !~ /^\s*$/ or tag("Statement") !~ /^\s*$/)
+define expenseChecker() = (tag("Receipt") !~ /^\s*$/ or tag("Invoice") !~ /^\s*$/ or tag("Statement") !~ /^\s*$/) and tag("Program") !~ /^\s*$/
 ; or payee =~ /NEVER CHARGED/
 
 account Expense:Main Org:Office Supplies

accounts/config/config-tags.ledger

@@ -39,3 +39,11 @@ tag Invoice
 
 tag IncomeType
     assert value =~ /^(Donations|RBI|UBTI)$/
+
+; Program tag must match the general format of a ledger account as an
+; assertion, but we at least check known names of programs, so that warnings
+; are produced if a new program never seen before is encountered.
+
+tag Program
+    assert value =~ /[ A-z0-9\-]+(:[ A-z0-9\-]+)*/
+    check  value =~ /^(Main Org:(Overhead|Direct Fundraising))$/

accounts/org/main-org.ledger

@@ -6,15 +6,18 @@
 2012-02-05 Office Supply Galore - Online Order
         ;Receipt: accounts/documentation/org/receipts/2012-02-05_office-supply-galore.txt
     Expense:Main Org:Office Supplies          $35.00
+        ;Program: Main Org:Overhead
     Liabilities:Credit Card:Visa             -$35.00
 
 2011/05/28 My Bad Billing Hosting - NEVER CHARGED
     Liabilities:Credit Card:Visa            $-100.00
     Expense:Main Org:Hosting                 $100.00
+        ;Program: Main Org:Overhead
 
 2012/01/01 My Bad Billing Hosting - REVERSAL - NEVER CHARGED
     Liabilities:Credit Card:Visa             $100.00
     Expense:Main Org:Hosting                $-100.00
+        ;Program: Main Org:Overhead
 
 2012-05-03 Sir Moneybags
         ;Entity: Sir-Moneybags
@@ -22,3 +25,4 @@
     Accrued:Accounts Receivable:Main Org  $100,000.00
     Income:Main Org:Donations            $-100,000.00
         ;IncomeType: Donations
+        ;Program: Main Org:Direct Fundraising

npo-ledger-cli-tutorial.md

@@ -261,6 +261,18 @@ relatively simple change to `config-tags.ledger`, though, to support other
 income types, or to change it entirely to handle use-cases other than USA
 Form 990 filing.
 
+#### Program Tag
+
+The `Program` tag is used primarily to track program activity for `Income:`
+and `Expense:` accounts.  This allows for knowing what particular initiative
+initiated the income (e.g., a specific fundraising campaign) and/or what
+particular program activity an expense is toward (e.g., funding travel to
+some specific conference).
+
+The Program tag is always a string with the same format as a Ledger CLI
+account (primarily for use with Ledger CLI's `--pivot` and `--group-by`,
+[as described later](#testing-program-success).
+
 ### Expense Account Documentation
 
 Each Expense account entries need to be tagged with an
@@ -312,6 +324,26 @@ However, going forward, you'd likely never enter anything the ledger
 the Expense did/should occur.  This use of `NEVER CHARGED` in the payee is
 thus deprecated.
 
+Analysis of the Data
+--------------------
+
+If this methodology is followed, Ledger can be used to analyze the financial
+data for the organization.
+
+### Testing Program Success
+
+If you use the [`Program`](#program-tag) tag effectively, you can easily test
+the successes of various fundraising programs with a command like this:
+
+    $ ledger -f accounts/books.ledger --pivot Program bal '/^Income/'
+
+Meanwhile, using the  [`Program`](#program-tag) tag for Expenses can help
+track what programs are costing with commands like hese:
+
+    $ ledger -f accounts/books.ledger --group-by 'tag("Program")' reg '/^Expense/'
+
+FIXME: example output
+
 Copyright and License of This File
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