[ADD] Expenses: Expenses analysis

closes odoo/documentation#15149

Signed-off-by: Felicia Kuan (feku) <feku@odoo.com>

content/applications/finance/expenses.rst

@@ -13,3 +13,4 @@ Expenses
    expenses/post_expenses
    expenses/reimburse
    expenses/reinvoice_expenses
+   expenses/expenses_analysis

content/applications/finance/expenses/expenses_analysis.rst

@@ -0,0 +1,75 @@
+=================
+Expenses analysis
+=================
+
+It is important for companies to track expenses so they have an understanding of their expenses and
+can identify trends. Expense reporting allows for detailed information, such as which expense
+categories are reimbursed the most, which employees incur the most expenses, and if there are any
+periods of time that tend to incur more expenses than others.
+
+View expense analysis report
+============================
+
+To view the default *Expenses Analysis* report, navigate to :menuselection:`Expenses app -->
+Reporting --> Expenses Analysis`. The :guilabel:`Expenses Analysis` report displays all expenses for
+the current year, in a stacked bar chart, grouped by month.
+
+.. image:: expenses_analysis/default-report.png
+   :alt: The default stacked bar chart for annual expenses, grouped by month.
+
+View expenses by employee
+=========================
+
+It is possible to view the data so that the total cost of expenses *by employee* is visible. To view
+the report in this way, navigate to :menuselection:`Expenses app --> Reporting --> Expenses
+Analysis`. Next, click the :icon:`oi-view-pivot` :guilabel:`(Pivot)` icon to view the data in a
+pivot table.
+
+This presents the data with the *employees* populating the rows, and the *total monthly expenses*
+populate the columns. Next, click :icon:`fa-minus-square-o` :guilabel:`Total` at the top of the
+monthly columns to hide the individual monthly totals, and present only the *total* amount for the
+year.
+
+To present the data in either ascending or descending total, click the :guilabel:`Total In Currency`
+box, and the information is organized first in ascending order, starting with the smallest amount.
+Click :guilabel:`Total In Currency` again to reverse the order, and present the highest amount
+first.
+
+.. example::
+   In this example it can be determined that :guilabel:`Mike Smith` has the highest amount of
+   expenses, totaling :guilabel:`4,216.44`. This is almost seven times higher than :guilabel:`Ronnie
+   Hart`, who has the second highest expenses, with a total of :guilabel:`644.74`.
+
+   .. image:: expenses_analysis/by-employee.png
+      :alt: A pivot table with the information shown by employee, in descending order.
+
+View expenses by category
+=========================
+
+It is possible to view the data so that the total cost of expenses *by category* is visible. To view
+the report in this way, navigate to :menuselection:`Expenses app --> Reporting --> Expenses
+Analysis`. Next, click the :icon:`oi-view-pivot` :guilabel:`(Pivot)` icon to view the data in a
+pivot table.
+
+This presents the data with the *employees* populating the rows, and the *total monthly expenses*
+populate the columns. Next, click :icon:`fa-minus-square-o` :guilabel:`Total` at the top of the
+employees column. Click :icon:`fa-plus-square` :guilabel:`Total` that appears in place of
+:icon:`fa-minus-square-o` :guilabel:`Total`, revealing a drop-down menu of options. Click
+:guilabel:`Category`, and the expense categories now populate the rows.
+
+Next, click :icon:`fa-minus-square-o` :guilabel:`Total` at the top of the months column to hide the
+individual months, and only show the annual total for each category.
+
+To present the data in either ascending or descending total, click the :guilabel:`Total In Currency`
+box, and the information is organized first in ascending order, starting with the smallest amount.
+Click :guilabel:`Total In Currency` again to reverse the order, and present the highest amount
+first.
+
+.. example::
+   In this example, it can be determined that the company spent the most on travel expenses, with
+   the expense category :guilabel:`[TRANS & ACC] Travel & Accommodation` incurring
+   :guilabel:`2,940.00` of expenses for the year. The company reimbursed mileage the least, with
+   only :guilabel:`229.69` in :guilabel:`[MIL] Mileage` expenses.
+
+   .. image:: expenses_analysis/by-category.png
+      :alt: A pivot table with the information shown by catrgory in descending order.