diff --git a/vendor/assets/javascripts/formula.js b/vendor/assets/javascripts/formula.js
index 3e5f139c7..75f6aa481 100644
--- a/vendor/assets/javascripts/formula.js
+++ b/vendor/assets/javascripts/formula.js
@@ -5337,6 +5337,8 @@
     };
 
     Formula.SLOPE = function (data_y, data_x) {
+      data_y = Formula.FLATTEN(data_y)
+      data_x = Formula.FLATTEN(data_x)
       var xmean = jStat.mean(data_x);
       var ymean = jStat.mean(data_y);
       var n = data_x.length;
diff --git a/vendor/assets/javascripts/ruleJS.js b/vendor/assets/javascripts/ruleJS.js
index 833f46f90..e37f836a2 100644
--- a/vendor/assets/javascripts/ruleJS.js
+++ b/vendor/assets/javascripts/ruleJS.js
@@ -913,7 +913,7 @@ var ruleJS = (function (root) {
       'ODD', 'OR',
       'PI', 'POWER',
       'ROUND', 'ROUNDDOWN', 'ROUNDUP',
-      'SIN', 'SINH', 'SPLIT', 'STDEVP', 'STDEVS', 'SQRT', 'SQRTPI', 'SUM', 'SUMIF', 'SUMIFS', 'SUMPRODUCT', 'SUMSQ', 'SUMX2MY2', 'SUMX2PY2', 'SUMXMY2',
+      'SIN', 'SINH', 'SLOPE', 'SPLIT', 'STDEVP', 'STDEVS', 'SQRT', 'SQRTPI', 'SUM', 'SUMIF', 'SUMIFS', 'SUMPRODUCT', 'SUMSQ', 'SUMX2MY2', 'SUMX2PY2', 'SUMXMY2',
       'VARP', 'VARS',
       'TAN', 'TANH', 'TRUE', 'TRUNC',
       'XOR'