Rotating door automation

Got the basic code started and tested.

Can anyone suggest an easy way to have the servo move more slowly?

#include <Servo.h> 

const int THRESHOLD = 680;   // an arbitrary threshold level that's in the range of the analog input
Servo myservo;  // create servo object to control a servo 
 
int LDRpin = 0;  // analog pin used to connect the potentiometer
int LDRval;    // variable to read the value from the analog pin 
 
void setup() 
{ 
  myservo.attach(9);  // attaches the servo on pin 9 to the servo object 
    // initialize serial communications:
  Serial.begin(9600);
} 
 
void loop() {
  // read the value of the LDR:
  int analogValue = analogRead(LDRpin);

  // if the analog value is high enough, turn on the Servo:
  if (analogValue > THRESHOLD) {
    myservo.write(180);
  } 
  else {
    myservo.write(0); //Reset the Servo if the value is too low
  }

  // print the analog value:
  Serial.println(analogValue);
  delay(150);        // delay in between reads for stability
}