diff --git a/lib/nbYear.ts b/lib/nbYear.ts
new file mode 100644
index 0000000..675060b
--- /dev/null
+++ b/lib/nbYear.ts
@@ -0,0 +1,18 @@
+export const nbYear = (p0: number, percent: number, aug: number, p: number): number => {
+
+  let year = 0
+
+  while (p0 < p) {
+    p0 += Math.floor(p0 * percent / 100) + aug
+    year++
+  }
+
+  return year
+}
+
+console.log(
+  nbYear(1500, 5, 100, 5000), 15
+)
+console.log(
+  nbYear(1500000, 2.5, 10000, 2000000), 10
+)