diff --git a/components/calcValues.vue b/components/calcValues.vue
index 67fb81e..aaa41c1 100644
--- a/components/calcValues.vue
+++ b/components/calcValues.vue
@@ -101,13 +101,14 @@ const changeParametres = () => {
         if (full_sections == 0) {
             length = total_length_mm - fence_length - fence_length
         }
-        if ((total_length_mm - ((full_sections * length) + (full_sections * fence_length) + fence_length)) < fence_length) {
+        let total_length_calc = (full_sections * length) + (full_sections * fence_length) + fence_length
+        if ((total_length_mm - total_length_calc) > 0 && (total_length_mm - total_length_calc) < fence_length) {
             full_sections -= 1
         }
     }
-
-    if (((full_sections * length) + (full_sections * fence_length) + fence_length) < total_length_mm) {
-        form_state.extra_section = total_length_mm - ((full_sections * length) + (full_sections * fence_length) + fence_length) - fence_length
+    let total_length_calc = (full_sections * length) + (full_sections * fence_length) + fence_length
+    if (total_length_calc < total_length_mm) {
+        form_state.extra_section = total_length_mm - total_length_calc - fence_length
     } else {
         form_state.extra_section = 0
     }