diff --git a/ausankey/ausankey.py b/ausankey/ausankey.py
index 301df56..be180f4 100644
--- a/ausankey/ausankey.py
+++ b/ausankey/ausankey.py
@@ -47,9 +47,6 @@ class Sankey:
     data : DataFrame
         pandas dataframe of labels and weights in alternating columns
 
-    aspect : float
-        vertical extent of the diagram in units of horizontal extent
-
     ax : Axis
         Matplotlib plot axis to use
 
@@ -160,7 +157,6 @@ class Sankey:
 
     def __init__(
         self,
-        aspect=4,
         ax=None,
         node_width=0.02,
         node_gap=0.05,
@@ -192,7 +188,6 @@ def __init__(
         sort="bottom",  # "top", "bottom", "none"
         valign="bottom",  # "top","center"
     ):
-        self.aspect = aspect
         self.ax = ax
         self.node_width = node_width
         self.node_gap = node_gap
@@ -227,20 +222,20 @@ def __init__(
     def setup(self, data):
         num_col = len(data.columns)
         data.columns = range(num_col)  # force numeric column headings
-        num_side = int(num_col / 2)  # number of stages
-        self.num_flow = num_side - 1
+        self.num_stages = int(num_col / 2)  # number of stages
+        self.num_flow = self.num_stages - 1
 
         # sizes
-        weight_sum = np.empty(num_side)
-        num_uniq = np.empty(num_side)
-        col_hgt = np.empty(num_side)
+        weight_sum = np.empty(self.num_stages)
+        num_uniq = np.empty(self.num_stages)
+        col_hgt = np.empty(self.num_stages)
         self.node_sizes = {}
         nodes_uniq = {}
-        for ii in range(num_side):
+        for ii in range(self.num_stages):
             nodes_uniq[ii] = pd.Series(data[2 * ii]).unique()
             num_uniq[ii] = len(nodes_uniq[ii])
 
-        for ii in range(num_side):
+        for ii in range(self.num_stages):
             self.node_sizes[ii] = {}
             for lbl in nodes_uniq[ii]:
                 if ii == 0:
@@ -263,20 +258,20 @@ def setup(self, data):
             self.node_sizes[ii] = sort_dict(self.node_sizes[ii], self.sort)
             weight_sum[ii] = pd.Series(self.node_sizes[ii].values()).sum()
 
-        for ii in range(num_side):
+        for ii in range(self.num_stages):
             col_hgt[ii] = weight_sum[ii] + (num_uniq[ii] - 1) * self.node_gap * max(weight_sum)
 
         # overall dimensions
         self.plot_height = max(col_hgt)
-        self.sub_width = self.plot_height / self.aspect
+        self.sub_width = self.plot_height
         self.plot_width = (
-            (num_side - 1) * self.sub_width
+            (self.num_stages - 1) * self.sub_width
             + 2 * self.sub_width * (self.label_gap + self.label_width)
-            + num_side * self.sub_width * self.node_width
+            + self.num_stages * self.sub_width * self.node_width
         )
 
         # offsets for alignment
-        self.voffset = np.empty(num_side)
+        self.voffset = np.empty(self.num_stages)
         if self.valign == "top":
             vscale = 1
         elif self.valign == "center":
@@ -284,11 +279,11 @@ def setup(self, data):
         else:  # bottom, or undefined
             vscale = 0
 
-        for ii in range(num_side):
+        for ii in range(self.num_stages):
             self.voffset[ii] = vscale * (col_hgt[1] - col_hgt[ii])
 
         # labels
-        label_record = data[range(0, 2 * num_side, 2)].to_records(index=False)
+        label_record = data[range(0, 2 * self.num_stages, 2)].to_records(index=False)
         flattened = [item for sublist in label_record for item in sublist]
         flatcat = pd.Series(flattened).unique()
 
@@ -299,6 +294,7 @@ def setup(self, data):
         color_palette = cmap(np.linspace(0, 1, len(flatcat)))
         for i, label in enumerate(flatcat):
             color_dict_new[label] = color_dict_orig.get(label, color_palette[i])
+        check_colors_match_labels(flatcat, color_dict_new)
         self.color_dict = color_dict_new
 
         # initialise plot
@@ -380,9 +376,6 @@ def subplot(self, ii, data):
             sort_nodes(labels_lr[1], self.node_sizes[ii + 1]),
         ]
 
-        # check colours
-        check_colors_match_labels(labels_lr, self.color_dict)
-
         # Determine sizes of individual subflows
         nodesize = [{}, {}]
         for lbl_l in nodes_lr[0]: