0003862: Straight Line Depreciation value calculation is wrong
[fa-stable.git] / fixed_assets / includes / depreciation.inc
index dda99f96639fbb8dffd30dac01377647fe309920..b63ad1a8eb527a5869db59a96d1d3864eefa9472 100644 (file)
@@ -62,20 +62,28 @@ function compute_gl_rows_for_depreciation($item, $no_months, $period) {
   $y = date('Y', strtotime($year['end']));
 
   switch ($item['depreciation_method']) {
-    case 'D':
-      $value = $item['material_cost'] * $item['depreciation_rate'] / 100 / 12;
-      break;
-
-    case 'S':
-      // depreciation_rate is the period here.
-      $done_months = months_between_dates($item['depreciation_start'], $item['depreciation_date']);
-      $remaining_months = $item['depreciation_rate'] * 12 - $done_months;
-      $value = $item['material_cost'] / $remaining_months;
-      break;
+       case 'D':
+               $line_value = $item['purchase_cost']*$item['depreciation_rate']/100/12;
+               $value = $item['material_cost'] * $item['depreciation_rate'] * $item['depreciation_factor']/100/12;
+               if ($value < $line_value)
+                       $value = $line_value;
+               break;
+
+    case 'S':  // purchase_cost stores start cost of item
+               $done_months = months_between_dates($item['depreciation_start'], $item['depreciation_date']);
+               $remaining_months = 12.0 * 100.0/$item['depreciation_rate'] - $done_months;
+               $value = $item['purchase_cost']*$item['depreciation_rate']/100/12;
+               break;
+
+       case 'N':
+               $N = $item['depreciation_rate'];
+               $done_years = months_between_dates($item['depreciation_start'], $item['depreciation_date'])/12;
+               $value = $item['purchase_cost']* ($N-$done_years)/($N*($N+1)/2)/12;
+               break;
 
     case 'O':
-      $value = $item['material_cost'];
-      break;
+               $value = $item['material_cost'];
+               break;
   }
 
   $next = next_depreciation_date($item['depreciation_date']);
@@ -84,6 +92,12 @@ function compute_gl_rows_for_depreciation($item, $no_months, $period) {
   $total = 0;
   $cnt = 0;
   for ($i=$m; $i < $m + $no_months; $i++) {
+
+       if ($item['depreciation_method'] == 'S') {
+               if ($cnt >= $remaining_months)
+                       $value = 0;
+       }
+
     $date = sql2date(date("$y-$i-t", strtotime("$y-$i-1")));
 
     $total += $value;
@@ -103,15 +117,11 @@ function compute_gl_rows_for_depreciation($item, $no_months, $period) {
 
     $cnt++;
 
-    if ($item['depreciation_method'] == 'S') {
-      if ($cnt >= $remaining_months)
-        $value = 0;
-    }
-    elseif ($item['depreciation_method'] == 'O') {
-      // depreciate only in the first month
-      $value = 0;
-    }
-  }
+       if ($item['depreciation_method'] == 'O') {
+               // depreciate only in the first month
+               $value = 0;
+       }
+ }
 
   return $rows;
 }