diff --git a/src/libsysprof-analyze/sysprof-xy-series.c b/src/libsysprof-analyze/sysprof-xy-series.c
index 8b42a688..75fcce1c 100644
--- a/src/libsysprof-analyze/sysprof-xy-series.c
+++ b/src/libsysprof-analyze/sysprof-xy-series.c
@@ -17,8 +17,11 @@
  *
  * SPDX-License-Identifier: GPL-3.0-or-later
  */
+
 #include "config.h"
 
+#include <math.h>
+
 #include "sysprof-xy-series.h"
 
 struct _SysprofXYSeries
@@ -30,14 +33,14 @@ struct _SysprofXYSeries
   GArray          *values;
 
   /* Our bounds for non-normalized values */
-  float            min_x;
-  float            min_y;
-  float            max_x;
-  float            max_y;
+  double           min_x;
+  double           min_y;
+  double           max_x;
+  double           max_y;
 
   /* Pre-calculated distance between min/max */
-  float            x_distance;
-  float            y_distance;
+  double           x_distance;
+  double           y_distance;
 
   /* Used for warning on items-changed */
   gulong           items_changed_handler;
@@ -73,10 +76,10 @@ warn_on_items_changed_cb (GListModel *model,
  */
 SysprofXYSeries *
 sysprof_xy_series_new (GListModel *model,
-                       float       min_x,
-                       float       min_y,
-                       float       max_x,
-                       float       max_y)
+                       double      min_x,
+                       double      min_y,
+                       double      max_x,
+                       double      max_y)
 {
   SysprofXYSeries *self;
 
@@ -89,6 +92,8 @@ sysprof_xy_series_new (GListModel *model,
   self->min_y = min_y;
   self->max_x = max_x;
   self->max_y = max_y;
+  self->x_distance = max_x - min_x;
+  self->y_distance = max_y - min_y;
   self->items_changed_handler =
     g_signal_connect (self->model,
                       "items-changed",
@@ -121,8 +126,8 @@ sysprof_xy_series_unref (SysprofXYSeries *self)
 
 void
 sysprof_xy_series_add (SysprofXYSeries *self,
-                       float            x,
-                       float            y,
+                       double           x,
+                       double           y,
                        guint            index)
 {
   SysprofXYSeriesValue value;
@@ -158,7 +163,7 @@ sysprof_xy_series_get_model (SysprofXYSeries *self)
 
 const SysprofXYSeriesValue *
 sysprof_xy_series_get_values (const SysprofXYSeries *self,
-                                guint                   *n_values)
+                              guint                 *n_values)
 {
   *n_values = self->values->len;
   return &g_array_index (self->values, SysprofXYSeriesValue, 0);
@@ -195,10 +200,10 @@ sysprof_xy_series_sort (SysprofXYSeries *self)
 
 void
 sysprof_xy_series_get_range (SysprofXYSeries *self,
-                             float           *min_x,
-                             float           *min_y,
-                             float           *max_x,
-                             float           *max_y)
+                             double          *min_x,
+                             double          *min_y,
+                             double          *max_x,
+                             double          *max_y)
 {
   g_return_if_fail (self != NULL);
 
diff --git a/src/libsysprof-analyze/sysprof-xy-series.h b/src/libsysprof-analyze/sysprof-xy-series.h
index db61d584..c0f16049 100644
--- a/src/libsysprof-analyze/sysprof-xy-series.h
+++ b/src/libsysprof-analyze/sysprof-xy-series.h
@@ -42,18 +42,18 @@ SYSPROF_AVAILABLE_IN_ALL
 GType                       sysprof_xy_series_get_type   (void) G_GNUC_CONST;
 SYSPROF_AVAILABLE_IN_ALL
 SysprofXYSeries            *sysprof_xy_series_new        (GListModel            *model,
-                                                          float                  min_x,
-                                                          float                  min_y,
-                                                          float                  max_x,
-                                                          float                  max_y);
+                                                          double                 min_x,
+                                                          double                 min_y,
+                                                          double                 max_x,
+                                                          double                 max_y);
 SYSPROF_AVAILABLE_IN_ALL
 SysprofXYSeries            *sysprof_xy_series_ref        (SysprofXYSeries       *self);
 SYSPROF_AVAILABLE_IN_ALL
 void                        sysprof_xy_series_unref      (SysprofXYSeries       *self);
 SYSPROF_AVAILABLE_IN_ALL
 void                        sysprof_xy_series_add        (SysprofXYSeries       *self,
-                                                          float                  x,
-                                                          float                  y,
+                                                          double                 x,
+                                                          double                 y,
                                                           guint                  index);
 SYSPROF_AVAILABLE_IN_ALL
 void                        sysprof_xy_series_sort       (SysprofXYSeries       *self);
@@ -64,10 +64,10 @@ const SysprofXYSeriesValue *sysprof_xy_series_get_values (const SysprofXYSeries
                                                           guint                 *n_values);
 SYSPROF_AVAILABLE_IN_ALL
 void                        sysprof_xy_series_get_range  (SysprofXYSeries       *self,
-                                                          float                 *min_x,
-                                                          float                 *min_y,
-                                                          float                 *max_x,
-                                                          float                 *max_y);
+                                                          double                *min_x,
+                                                          double                *min_y,
+                                                          double                *max_x,
+                                                          double                *max_y);
 
 G_DEFINE_AUTOPTR_CLEANUP_FUNC (SysprofXYSeries, sysprof_xy_series_unref)
 
diff --git a/src/libsysprof-gtk/sysprof-depth-layer.c b/src/libsysprof-gtk/sysprof-depth-layer.c
index 5456076d..67829580 100644
--- a/src/libsysprof-gtk/sysprof-depth-layer.c
+++ b/src/libsysprof-gtk/sysprof-depth-layer.c
@@ -47,7 +47,7 @@ sysprof_depth_layer_snapshot (GtkWidget   *widget,
   SysprofDepthLayer *self = (SysprofDepthLayer *)widget;
   const SysprofXYSeriesValue *values;
   guint n_values;
-  float min_x, max_x;
+  double min_x, max_x;
   int line_width;
   int width;
   int height;