diff --git a/Project.toml b/Project.toml
index 3c42253..7b073d8 100644
--- a/Project.toml
+++ b/Project.toml
@@ -15,7 +15,7 @@ StatsModels = "3eaba693-59b7-5ba5-a881-562e759f1c8d"
 
 [compat]
 Compat = "^3.0"
-DataFrames = "0.19, 0.20, 0.21"
+DataFrames = "0.21, 0.22"
 DataStructures = "0.17, 0.18"
 Distributions = "0.20, 0.21, 0.22, 0.23, 0.24"
 Formatting = "^0.3.3, 0.4"
diff --git a/src/QuickTools.jl b/src/QuickTools.jl
index 91fe677..abe19d8 100644
--- a/src/QuickTools.jl
+++ b/src/QuickTools.jl
@@ -93,7 +93,7 @@ end
 function tabulate(df::AbstractDataFrame, field::Symbol)
 
     # Count the number of observations by `field`
-    tab = by(df, field, _N = field => length)
+    tab = combine(groupby(df, field), field => length => :_N)
 
     # Construct a Frequency Column
     sort!(tab, field)
@@ -116,7 +116,7 @@ function tabulate(df::AbstractDataFrame, field1::Symbol, field2::Symbol)
     # Count the number of observations by `field`
     fields = vcat(field1, field2)
     df     = dropmissing(df[!,fields], disallowmissing=true)
-    tab = by(df, fields, _N = field1 => length)
+    tab = combine(groupby(df, fields), field1 => length => :_N)
     sort!(tab, [field1, field2])
 
     # Put it into wide form