Index exceeds matrix dimensions. Why?

close all;
clear all;
clc;

%load data & display
dataset= xlsread('DSN OFFSET.xlsx','R0'); 
disp(dataset);

%read data
z = dataset(3:53,1);
x = dataset(1,2:53);
y = dataset(3:53,2:53);

[Orangelynx]

don't want to be the jerk but how is anyone supposed to know what's wrong here? we have no clue about the data you are dealing with. for starters you may try

size(dataset)

to see what dimensionality the variable has and if it complies with what you expect it to be.